This section is for storm chases done in the central / Midwestern United States during the year of 2017. This includes all storm chasing activities (including any major chase "expeditions") during the year of 2017 in the central USA (aka "Tornado Alley"). For 2017, all chases in the central USA will be logged in this section, with many of the chases being possible "spot" chases / major severe weather "setups" chased. Here you should find many pictures of lightning, tornadoes, hail, strong winds, along with many severe thunderstorm elements. Keep in mind that this chase log is scientific evidence and portrays my on-going storm chasing research. It has been placed on this page for easy reference and meteorological interests. Please do not plagiarize or copy this document to other sites for distribution.

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STORM CHASING - CENTRAL UNITED STATES - 2017 CHASE LOG

The terrifying mass of fast moving clouds, dirt, and debris churns over an open field and takes aim on the eastern side of Canton, Texas during the late afternoon of April 29, 2017. This was a powerful wedge tornado that finished toppling high voltage transmission lines just east of Highway 19, and is continuing north and northeastward towards Interstate 20 and the unfortunate towns of Canton and Fruitvale, Texas. The tornado was rated a high-end EF-3 tornado, with winds well over 160 MPH, and caused 5 deaths and dozens of injuries along a path 51 miles long and after being on the ground for over an hour. The tornado was up to a mile wide in some places. This scene always causes me and other storm chasers to have a strong respect for the destructive power, then sadness as lives are lost and changed forever. While taking the above picture (from video), and from less than a mile from the tornado core, the sound resembled a loud train with a low "growling" sound, with vibration felt in my chest as well as the ground. My ears also popped. Luckily I was able to keep my distance in the "bearís cage" of the supercell between the RFD hook and tornado core flow, and wound up with this absolutely incredible footage. At the same time - Always keep the people affected by these storms in out hearts and prayers.


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ABOUT THIS CHASE LOG FOR THE MIDWEST

This is a chase log for any chases during 2017 in the Midwest and Central United States that were conducted as "spot" chases as well as any dedicated chase trip. Each chase section within this area will have its own details and such for that particular chase. This area was set up in the spring of 2017 and is for any chase that was conducted in the US Plains and Midwest. Equipment use in such chases range from cell phone to HAM radio communications, digital / still cameras, video (SD) and high-definition (HD) camcorders, and data logging / GPS via laptop computer. Storm chasing involved driving in harsh conditions and / or for long periods of time.

All chases and observations are in chronological order and a chase number is assigned to each entry. Please bear in mind that all observations adhere to modern storm analysis standards and do not include all storms that occurred in a given area for a particular chase period.

Any kind of storm such as a thunderstorm, tornado, waterspout, tropical cyclone, and extratropical storm can be chased or observed. I have tried to keep this log of any storms that I have observed as accurate as possible, while using terms and expressions to abide by those used by most meteorologists and storm spotters today.

Storm chasing and observation can be extremely dangerous and may result in serious injury or death. I have received intermediate and advanced training for storm spotting in 1996. I strongly urge anyone who is to try their hand at storm spotting to get training before doing so. You must also have a good understanding of meteorology and storm dynamics. "If you don't know what you're doing, Don't do it!" Contact your local National Weather Service office for information on storm spotting and about training to become a Skywarn storm Spotter.


CHOOSE A VIDEO CLIP BELOW - LINKS TO YOUTUBE

Large Tornadoes In Van Zandt County (TX) On April 29, 2017


CHASE MAP FOR MARCH 23-30, 2017

This is a chase map for the chase from March 23 through March 30, 2017. The chase track is in blue (which includes the driving portions of the trip), and the flight (to and from Fort Lauderdale, Florida and Dallas, Texas) is in green. The target areas appear as yellow outlines for the main chase days, with storm intercepts denoted by the red "X's".


CHASE TRIP CHRONOLOGY FOR MARCH 23-30, 2017

This chase trip was based on a progressive pattern in severe weather more typical of a late spring setup than early spring. The trip was originally to be from March 23rd returning the 27th, but was extended to the 30th. March 23 was the first travel day of the trip, with chasing (target area was in the Texas Panhandle) commencing right after arrival from Fort Lauderdale, Florida to Dallas, Texas. After arriving in Dallas, I picked up the rental car, a 2017 Hyundai Accent, and immediately left the area via I-35E and north to Denton and Highway 380 west. The target area forecasted was anywhere near Amarillo, a long 5 hour drive from Dallas! I headed west on 380 to 277, and continued on that highway through Wichita Falls and all the way to I-40 in Amarillo between 6 and 7 PM. Storms were intercepted just west of Amarillo by that time. Meanwhile, the Storm Prediction Center (SPC) had the target area within a slight risk, with a 15% wind and hail probability. Tornado probability was just 2% due to limited low level moisture during arrival of the upper level support. The SPC issued Mesoscale Discussion MCD 311 and subsequent severe thunderstorm watch 78 valid until 10 PM CDT. After chasing the storms, I headed back into Amarillo for the night off I-40.

March 24 was a very long chase back to central and eastern Texas basically backing down 277 and 380 through Denton and east of there. I left Amarillo at about 7 AM, passing through heavy lunch hour traffic east of Denton on 380 through McKinney by about 1 PM. I continued east to I-30 and exited to take Highway 67 / 259 south once ahead of the on-going thunderstorms. I bumped east on 11, then 59 south to I-20 near Marshall, Texas. The SPC had an enhanced risk in far eastern Texas, with a 10% tornado, 15% Hail, and 30% wind in their probabilities. MCD 320 was issued for my area along I-20 near the TX / LA border (along with other MCDs for surrounding areas). Tornado watch 82 was eventually issued (between other areal outlooks) for this primary target area, valid until 3 AM CDT the next day. I waited until sundown and bumped into Louisiana along I-20 to near Shreveport. Storms remained weak and disorganized until upper wave arrival after dark, with only multi-cellular bow segments and rain wrapped areas of rotation affecting the area. Unwilling to chase severe storms after dark, I abandoned the chase by heading back west on I-20 into Dallas by late evening, eventually heading up I-35 into Denton, Texas for the night.

March 25 was an off day with a lazy reposition from Denton, Texas to Oklahoma City, OK anticipating the next major chase day (where SPC already had an enhanced risk on their day 2 outlook for March 26) there and points southwest. I also saw yet another disturbance over the central Pacific Ocean, opting very good chase opportunities early in the next week once it reaches the USA. I decided to extend the trip to return on March 30th (instead of the 27th) via a reservation change. I reached Oklahoma City via I-35 to I-44 by afternoon and spent the night there.

The following day, March 26 was a moderate-risk chase day in south-central Oklahoma. The SPC had a tornado probability of 10%, along with a 45% (hatched for significant) hail, and 30% wind (also hatched for significant) in their 1630z moderate risk outlook. Based on morning forecasting, the target area and plan of the day was to be anywhere along and west of I-35 and towards the Sulphur / Ada area which would be ahead of the dryline bulge. I left just before noon and down I-44 to I-40 west into El Reno, paying a tribute to the Tim Samaras group memorial (Radio Road), and continuing south on Highway 81 to Chickasha for late lunch. By late afternoon, I continued south and east on Highway 19 and I-35 to Davis to wait for storm initiation west of that area. Meanwhile the SPC issued MCD 335 and subsequent tornado watch box valid until 11 PM CDT. Storms began initiating near from near Tatums and highway 7, and eastward to near Byars and Lula and eastward to Highway 75 east of Ada, where the storms matured and produced tornadoes. A very well done forecast and target area! After chasing, I headed down highway 75 to Coalgate for fuel and to upload footage. I then headed west on Highway 31 to Highways 48 and 7, then Highway 377 south to near Highway 32 and Marietta eventually to I-35 south. I spent the night just north of Dallas, TX. The next day was to be an off day.

March 27 was an off day and included a vehicle exchange and re-position to Wichita Falls later in the day. To extend my trip, I returned the first vehicle as originally scheduled and rented another (both were 2017 Hyundai Accents) with a different company to save costs. A minor hail damage claim was opened on the first returned vehicle. I left Dallas via I-35 north after late lunch and Highways 380 and 277 northwest into Wichita Falls for the night. The following day was expected to be another very active severe weather chase day from that area, and points southwestward.

March 28 was a very busy chase day, with both frustration and a "tornado finale" later on in the chase. I forecasted and left Wichita Falls during the late morning via Highway 277 west towards Vernon. There were already on-going storms along the developing dryline due to weak capping so the forecast and target kept shifting southward into the better moisture and heat energy (CAPE). After lunch in Vernon, I headed west via Highways 70 and 62 to check a storm near Matador. The SPC had a moderate risk for this day, with tornado probabilities at 10%, Hail hatched for significant at 45%, and wind at 30%. MCD 355 was issued, then tornado watch box 95 valid until 11 PM CDT. The setup was not good up there, so I headed back east through Paducah then Highway 83 south passing a tornadic storm near Guthrie, then east on 380 to Highway 6 out of Aspermont to Stamford where a large tornado was intercepted. The storm was followed up around Lake Stamford from Avoca to 380 again, then east to Throckmorton where it was outflow dominated. The chase was wrapped up via Highway 79 out of Throckmorton and Highway 114 in Olney southeast to 380 in Jacksboro, then continuing on Highway 380 east through Decatur and spending the night in Denton, Texas. This chase day came to a sad end hearing three storm chasers died in a car accident early in the afternoon near Spur, Texas.

The last real chase day was March 29. This day looked much better a few days back, but turned out to be much farther east, and with more of a widespread severe storm event than tornadoes. Regardless, I was out one more day, so I decided to chase. The storms expected were to be in a rather messy area of severe storms extending from NW Missouri / NE Kansas southward near Houston. I forecasted and decided to stay away from the mess of storms in poor chase terrain (such as W Arkansas) and hope for more photogenic LP type storms along the dryline in far NE Texas. I chose Texarkana as the target, and headed there by leading Denton early on Highway 380 east, picking up I-30, and heading into Texarkana by lunch time. The forecast wound up playing out as expected, with a photogenic LP storm observed in NE Texas late in the day (near De Kalb along Highway 82), while linear and messy convection occurred to the northeast and south. SPC had the area in a Enhanced risk, with a 10% tornado area in Arkansas, surrounded by a very large 5% area. Hail and wind probabilities were both 30%. MCD 371 and 372 was issued, and a few tornado watches were issued, with my target being in tornado watch box 100, valid until 12AM CDT the following day. After chasing, I headed south out of De Kalb on Highway 259 to I-30, then back east to Highway 380, spending the night in Mc Kinney, Texas.

March 30 was the final day of this extended and quite interesting chase trip. This was strictly a travel day, and involved packing up early in the morning and heading back to Dallas via Highway 75 to I-635 / I-35 into the Love Field Airport area to return the rental car. I flew back to Fort Lauderdale, Florida (moderate to severe turbulence was also encountered crossing the area of "messy" convection over Louisiana and Mississippi), returning there by noon. This was the end of this chase trip. Total mileage was around 3,005 miles (with 1,895 on the first rental, and 1,110 on the second).


MARCH 23-30 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME / BASE CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURADEERFIELD BEACH, FLKG4PJN3-23 TO 3-30IT CONSULTANT


CUMULATIVE STORM REPORTS FOR MARCH 23-30, 2017

This is a comprehensive / cumulative map of all Storm Prediction Center (SPC) storm reports for March 23-30, 2017. In this cumulative storm reports, combining data from 8 images from SPC for each day, a red dot denotes a tornado report, a blue dot a damaging severe wind report (58 MPH and up), and a green dot a severe hail report (1" and larger). Significant wind (65 knots and up) and significant hail (2" and larger) is denoted by a black square and triangle, respectively. There were a total of 1,072 severe weather reports during this period (consisting of 53 tornado, 516 wind, and 503 hail reports). Out of the wind and hail reports, 11 significant wind and 39 significant hail reports were tabulated during this time period.


DETAILED CHASE LOG FOR MARCH 23-30, 2017

1). March 23, 6:30 PM - Interception and observation of a severe thunderstorm in Oldham / Potter County, Texas and west of Amarillo along Interstate 40. The storm was a supercell storm developing on the south side of a cluster of strong and severe thunderstorms. The core of the storm was not penetrated, but most likely contained large hail. Conditions encountered were occasional lightning, some rain, and strong winds gusting near 60 MPH. Dust was kicked up making it difficult to see the storm structure, but striations and the RFD clear slot was noticeable. Conditions causing the storm were a dryline, low pressure system, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was valid for the area until 10 PM CDT.

2). March 24, 8:30 PM - Observation of a strong to possibly severe thunderstorm along I-20 and west of Marshall in Harrison County, Texas. The storm was a multicell segment of storms that acquired a pronounced bow structure after passing by. Very heavy rains, lightning, and winds near 45 MPH were encountered with this line segment. A possible tornado also developed in the northern portion of this bow segment from Marshall and northeastward. This would have been entirely rain wrapped and not visible in daylight anyway. Conditions causing the storm were a pacific front (overtaking a dryline), low pressure trough, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 3 AM CDT the following day.

3). March 26, 1:00 PM - Observation of a strong to severe thunderstorm from Chickasha, Oklahoma in Grady County and near Highway 81. The storm was part of an elevated complex of strong and severe thunderstorms. Light to moderate rain, occasional lightning, and pea to dime sized hail was observed with this storm. Conditions causing the storms were a low level jet and strong upper trough. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills.

4). March 26, 5:00 PM - Observation and penetration of a very severe and tornadic thunderstorm from near Tatums, Oklahoma to near Byars and Konawa, and in Garvin and McClain counties near Highways 19, 133, and 59. This storm was a classic supercell storm. The core was not directly penetrated but hail in excess 2" (most stones were smaller and quarter sized) was observed on the edge of the hail core, causing minor damage to the vehicle. An isolated hail stone to tennis ball sized was also noted smashing into the road. A low wall cloud and funnel was noted near Pauls Valley. A developing weak tornado was briefly visible with this storm south of Konawa looking northwest from Highway 3W. The storm also contained heavy rains, 50 MPH winds, and frequent lightning. Conditions causing the storm were a dryline, low pressure area, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

5). March 26, 7:00 PM - Observation of an extremely severe and tornadic thunderstorm to the east of Ada, Oklahoma in Ponotoc County near Highway 48 north of Lula. The storm was an LP to classic supercell thunderstorm. The storm had a striking visual appearance, appearing as a "spaceship" with striated updraft and vault, when viewed from the east. A well documented tornado was also observed with this storm as well north of Lula. The core of the storm was not penetrated, but contained hail exceeding baseball sized. Impact sounds from the hail (sounded like gun shots) could be heard to my northwest on the edge of the hail core at 1-2 mile distance! Largest hail at my location was widely spaced quarter sized, along with frequent lightning, light rain, and 50 MPH winds (mainly inflow). The tornado itself was a cone funnel that evolved to a long rope that wrapped around a portion of the wall cloud. This feature remained over rural areas and did no damage. Conditions causing the storm were a dryline, low pressure area, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

6). March 26, 8:00 PM - Observation and penetration of a strong thunderstorm to the southwest of Coalgate, Oklahoma along Highway 31 in Coal County. This storm was part of a multicell line of strong and severe storms. Frequent lightning (with some close hits), torrential rains, 50 MPH winds, and small hail were observed with this storm. Conditions causing the storm were a pacific front (overtaking a dryline), low pressure trough, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

7). March 28, 3:30 PM - Observation of a severe thunderstorm to the west and northwest of Matador, Texas in Motley County and near Highways 62 and 70. The storm was a slightly elevated HP supercell storm. A large slowly rotating wall cloud was observed with some small funnels and possible a brief weak tornado. The storm was in very poor visibility and was undercut by cooler air and in an environment of more stable air. The core (containing golfball sized hail) was not penetrated. Lightning and moderate rain was encountered. Conditions causing the storm were a dryline, low pressure area, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

8). March 28, 4:30 PM - Observation and penetration of a very severe and possibly tornadic thunderstorm to the south and southwest of Guthrie, Texas and west of Highway 83 in King County. This storm was a powerful HP supercell, with a wall cloud that rapidly rotated and occluded. When viewed from the east and northeast, looking WSW, a brief tornado was observed with dust and tagging rain curtains before being obscured by (wet) RFD rain wrap (descending reflectivity core). Small hail, 60 MPH winds, frequent lightning, and torrential rains were also observed while proceeding southward through the RFD winds as the storm was completely rain wrapped. Conditions causing the storm were a dryline, low pressure area, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

9). March 28, 6:00 PM - Interception, observation, and penetration of an extremely severe and tornadic thunderstorm in Haskell County, Texas near Highways 277 and 6 from Stamford to east of Haskell. The storm was part the "tail end Charley" cluster of supercell storms at the southern end of a messy cluster of supercells arcing along a dryline bulge. One supercell in this cluster (there were three with the strongest tornadic one in the middle) was a cyclic supercell storm. A large stove pipe tornado was encountered with this storm once clearing the precipitation core from the north (I managed to miss the large hail) through the south side of Stamford. Fortunately, the tornado missed the town. The storm was followed north and east around Lake Stamford and it subsequently became outflow dominated northwest of Throckmorton, Texas. Strong winds to 70 MPH, small hail, and frequent lightning was also observed with this storm. Conditions causing the storm were a dryline, low pressure area, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 11 PM CDT.

10). March 29, 2:30 AM - Observation of a strong to possibly severe thunderstorm off I-35 at a stationary location (hotel) in Denton, Texas in Denton County. The storm was part of a line of strong and severe thunderstorms moving through the area. Heavy rains, small hail, frequent lightning, and winds to near 60 MPH were encountered. Conditions causing the storm were a low pressure trough, upper trough, and low level jet. A 2017 Hyundai Accent was involved with chasing these storms. A severe thunderstorm watch was also valid for the area until 4 AM CDT.

11). March 29, 7:00 PM - Observation of a strong thunderstorm near De Kalb in Bowie County, Texas and along and to the north of Highway 82. The storm was a low topped LP supercell with a flared out base, corkscrewed updraft, and core of small hail. The storm core was not encountered. Conditions causing the storm were a dryline, low pressure trough, upper trough, and surface heating. A 2017 Hyundai Accent was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 12 AM CDT the following day.

This concludes the chase log for the central US Plains (including chases in Arkansas, Louisiana, Oklahoma, and Texas) chase trip for March 23-30, 2017. The summary includes a total of 11 observations, out of which there were 9 severe thunderstorms and 2 strong thunderstorms. 3 tornadoes were observed from three of the severe storms. The main chase vehicle conducting this chase were two 2017 Hyundai Accents (one for March 23rd to the 27th, and another from the 27th to the 30th, both nearly identical). This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.


GALLERY FOR MARCH 23, 2017

March 23 was a chase day with a long drive to the Amarillo area after getting into Dallas at around noon. In the images above, the SPC forecast only showed a 2% tornado probability in a large slight-risk area (moisture was limited). The plan of the day, time-permitting, was to target the southern portions of the slight-risk area, and Amarillo was reached by storm initiation. In the middle image is the SPC mesoscale discussion (MCD 316) issued for the area for the severe weather outlook. To the right, is a base-reflectivity radar image from Amarillo showing a tail-end "Charley" type supercell storm briefly firing on the dryline and in the targeted area.

Here is a view of Dallas, Texas while approaching Love Field airport on March 23, 2017. This was the start of the trip, and a rather rushed plan to get to the Texas panhandle as quick as possible.
This is a view looking west on I-40 towards Amarillo, Texas. The storm complex is still west of the city, and the anvil blowoff can be seen streaming overhead late in the day on March 23, after a long drive from Dallas.
Here is a view of the flanking line and updraft (center and right of the picture) of a supercell storm just west of Amarillo, Texas on March 23. The visibility is compromised by blowing dust.
The supercell weakens, and evolves to a line segment as if moves to the northeast of Amarillo, Texas and away from the dryline / moisture axis during the evening of March 23.


GALLERY FOR MARCH 24, 2017

March 24 was a long range chase that failed to verify to expectations in far east Texas, after a long drive from the Amarillo area. In the image above, tornado watch 82 is shown, issued by the SPC. The visible satellite is in the middle image, showing the annotated target area in eastern Texas, with the exit region of the jet stream. Note the massive vorticity associated with the cold core (upper level low) near the eastern Texas Panhandle! To the right, is a reflectivity radar image (out of Shreveport, Louisiana) of the bow segment that finally formed in far eastern Texas well after dark.

Mid to high altitude cloud formations associated with a strong jet stream and exit region aloft over central / eastern Texas on March 25. This is part of the storm system that provides the upper level air support for severe weather.
Disorganized severe storm developing near I-30 and Marshall, Texas. This will be a bow segment to produce damaging winds after dark on March 25.


GALLERY FOR MARCH 25, 2017

March 25 was strictly a re-position day from the Dallas, Texas area to Oklahoma City, Oklahoma. It was not a chase day, but in the images above, we see the weakening disturbance from the prior day moving off to the east, with the SPC slight-risk and 2% tornado probabilities in the left and middle images, respectively. To the right the upper wave and storm system are shown on the visible satellite image weakening over the Midwestern states.

Here is a view of Oklahoma City, Oklahoma (with the Devon Energy building, the tallest skyscraper in the central USA, to the left) while re-positioning north there on the off day of March 27.


GALLERY FOR MARCH 26, 2017

March 26 was a rather busy chase day with tornadic supercells intercepted in central Oklahoma. To the left image, the SPC mesoscale discussion (MCD 335) is shown, with the tornado probabilities highest along the I-35 corridor pretty much near Ada and Ardmore, Oklahoma. In the middle image, tornado watch box 86 is shown. To the right, the radar image (base reflectivity) out of Oklahoma City shows the powerful tornadic supercell near and east of Ada, Oklahoma late in the day.

Supercell storms initiating along the dryline west of I-35 and northwest of Davis, Oklahoma during the afternoon of March 26.
Large rotating wall cloud / funnel approaching Pauls Valley, Oklahoma on March 26.
Hail shaft and greenish hue (and UDI - updraft-downdraft interface) of the first supercell storm approaching Pauls Valley, Oklahoma on March 26.
Hail around the size of golf balls covering the roadway northeast of Pauls Valley, Oklahoma on March 26. This caused minor damage to the rental vehicle.
Developing weak tornado (to far lower right) and updraft tower of the first supercell storm passing to the northwest of Ada, Oklahoma (NE of Pauls Valley) on March 26. Note the striations in the upper part of the picture! This storm would soon weaken due to a strong storm developing southeast of Ada.
Intense and very photogenic LP (to classic) second supercell storm just to the east of Ada, Oklahoma on March 26. The view is to the west.
Developing tornado east of Ada, Oklahoma on March 26.
Maturing tornado east of Ada, Oklahoma on March 26.
Tornado confirmed via debris cloud on ground, despite the visible funnel being discontinuous. This was east of Ada, Oklahoma on March 26.
Lightning illuminating the eastern side of the HP supercell as it continues to the northeast into east-central Oklahome after dark on March 26.


GALLERY FOR MARCH 27, 2017

March 27 was not a chase day, and involved a reposition to west-central Texas from Dallas after a rental vehicle exchange. In the images above, we can see the SPC enhanced risk area farther east in the Midwest in the left image. In the middle image, a mesoscale discussion (MCD 342) was issued but most convection that day was disorganized. The right shows the weakening frontal system moving off to the east as well in the visible satellite.

Here is a picture of myself, while driving to Wichita Falls, Texas, after exchanging the car rental for a longer stay. March 27 was an off day.


GALLERY FOR MARCH 28, 2017

March 28 was a very busy chase day, with the best storms intercepted in west-central Texas and tornadoes observed there. In the left image, the SPC tornado product is shown, with a 10% probability of tornadoes as part of a moderate risk outlook. The middle image shows a visible satellite and supercell storms developing, with the tornado producing ones annotated. To the base reflectivity image at the right, a cluster of "tail-end Charley" supercells is shown, with the area of the storm complex producing tornadoes circled.

Poorly defined HP supercell (you can barely see the occlusion in the center of the picture) west of Matador, Texas on March 28. The storm was tornado warned at the time.
Wall cloud looking southwestward from southeast of Guthrie, Texas on March 28.
Wall cloud, developing weak tornado (center), and wet RFD occlusion (HP supercell notch) looking southwestward from southeast of Guthrie, Texas. During afternoon of March 28.
View of large wall cloud and RFD area from the town of Stamford, Texas on March 28.
Wide view of intense RFD cut and developing tornado to the far left in the picture looking southeastward of Stamford, Texas during the afternoon of March 28.
Intensifying stovepipe tornado and wall cloud to the east of Stamford, Texas on March 28.
View of stovepipe tornado to the east of Stamford, Texas on March 28.
Closer shot of stovepipe tornado and debris cloud to the east of Stamford, Texas on March 28.
Tornado begins to lift and rope out to the northeast of Stamford, Texas on March 28.
Supercell storm begins to become outflow dominant near Lake Stamford in Haskell County, Texas on March 28.
Supercell storm evolves to a line segment north of Throckmorton, Texas late on March 28.


GALLERY FOR MARCH 29, 2017

March 29 was the last full day available for chasing in this trip. My plan was to avoid the better tornado probabilities in the bad chase terrain in Arkansas (which also verified poorly for tornadoes) as well as the messy HP convection in SE Texas. The goal was to intercept LP supercells on the dryline / Pacific front on the western edge of the low level moisture axis. The target area is annotated in the images above, with the SPC tornado probabilities in the left image, tornado watch 100 in the middle image, and visible satellite to the right showing the LP storms firing in the target area late in the day.

View of developing LP supercell storm with base (note RFD to left developing) near De Kalb, Texas on March 29.
View of LP and low-topped supercell storm with hail core and rain-bow through RFD as is passes north of De Kalb, Texas on March 29.
Here is another view of an LP supercell storm near De Kalb, Texas on March 29.
View of mid to high altitude cloud formations associated with the core of the jet stream passing overhead. The lower clouds are associated with a dryline / Pacific cold front. The view is looking west on I-30 in NE Texas.


GALLERY FOR MARCH 30, 2017

March 30 was a travel day from Dallas, Texas returning back to Fort Lauderdale, Florida. In the images above, the SPC outlook is shown for the day to the left. In the middle is the visible satellite, showing clearly the powerful storm system (wave cyclone) over the middle of the USA. To the right is the turbulence forecast product from the ADDS (NWS Aviation forecasts) and pilot reports, showing numerous reports of moderate to even severe turbulence over the northern Gulf of Mexico and Gulf states associated with the powerful southern branches of the active jet stream.

Flying back across the powerful upper level storm system and around convection over the northern Gulf of Mexico and deep south between Dallas, Texas and Fort Lauderdale, Florida. The view is approaching the system from the west, and the anvil blowoff can be seen in the distance.
Moderate to heavy turbulence rocks the plane as it overflies the Gulf states and passes through the upper trough and convection.


CHASE MAP FOR CHASE EXPEDITION 2017

This is a chase map for the main chase "expedition" for 2017. This was an extended chase trip from April 17 through June 26, with any off-time in between spent either in Chicago or Florida (if outside "Tornado Alley"). The trip started by driving out from Florida on April 17, 2017 and the first actual chase day being in SE Nebraska on April 19th. The chase track (including driving to and from the central USA) is in blue. Any flights, particularly to and from Chicago (the "base" city for this trip) to South Florida, appear as the green paths. No target areas are shown on this map due to the lengthy nature of this chase trip (refer to the chronology below for those details). Storm intercepts denoted by the red "X's". Total mileage logged was 23,701 miles on the 2016 Jeep Wrangler.


CHASE TRIP CHRONOLOGY FOR CHASE EXPEDITION 2017

This is the main storm chasing "expedition" for spring of 2017. The trip was from April 17 through June 26, 2017 with any off-time spent either in Chicago or back in South Florida. The trip started by preparing my personal chase vehicle, a 2016 Jeep Wrangler, and driving out of south Florida on April 17, 2017. Going up I-95, then the FL Turnpike to I-75 (through Orlando), and spending the night in Gainesville, Florida. On April 18, I continued up I-75 through Atlanta to I-24, taking that to I-57 and I-64, eventually spending the night on the NW side of Saint Louis, Missouri. This was anticipating the first chase and target area near SE Nebraska / NW Missouri / SW Iowa on the 19th. Since this is going to be a rather lengthy chase log, some details will be summarized and any radar or SPC graphics pertaining to an important chase will be in the gallery sections.

April 19 was the first chase day of this chase expedition. After forecasting, it appeared the best place to be was anywhere from SW Iowa and into SE Nebraska with a triple point type low pressure setup and Pacific cold front. The storm prediction center (SPC) had this area in an enhanced-risk, with tornado probabilities of 10%, wind at 15%, and hail at 30% (and hatched for significant). I headed out of Saint Louis on I-70 to Kansas City, then north on I-29 to near highway 136 to go west into Nebraska. SPC had mesoscale discussion (MCD) 519 and tornado watch box 148 valid until 10 PM CDT by late afternoon. Storms, one producing a possible tornado, were intercepted SE of Lincoln, NE and west of highways 75 and 34 near Palmyra. Storms were followed eastward into SW Iowa and NW Missouri along Highway 2 and near 71. After wrapping up the chase, and with the possibility of storms farther south over the next couple of days, I decided to spend the night in Topeka, Kansas. I headed back west on Highway 136 to 75, then south into Topeka.

April 20 was both a re-positioning day, but had some marginal chase potential stretching from SW Oklahoma and into NW Texas. The SPC had this area in a slight risk, with tornado probabilities under 2%, wind at 5%, and hail at 15%. The plan was to head to that area, with elevated severe storms expected near or after dark, with that leaving me in good position for the next chase day (April 21). I headed out early of Topeka via I-335, then I-35 south through Wichita, ultimately taking I-44 southwest through Oklahoma City, reaching Lawton by mid to late afternoon. I headed west out of Lawton to Highway 183, then south into Texas near Vernon and waited near Mabelle along Highway 82. A brief storm developed to the southwest near Haskell County, but I only briefly followed it south of Munday along 277. Since I planned to stay in Lawton, I backtracked to near the red River up 183 and 283 north of Vernon, TX and south of Altus, OK. An elevated supercell storm was encountered in this area after dark, at about 10 PM. The SPC also had MCD 529 and severe thunderstorm watch 152 valid until 5 AM CDT the next day for this area. After chasing, I headed back east on Highway 5, then 183 north to 62 east, and reached Lawton around midnight for the night.

April 21 was a pretty good chase day, mainly in north-central Texas starting in Gainesville, proceeding near the Red River, and eastward to near Hugo, Oklahoma. I woke to a severe (outflow dominant) storm in Lawton, forecasted, and left the area by about 11 AM via Highway 7 east. On Highway 81, I headed south towards Bowie, Texas after stopping in Duncan, Oklahoma. Once in Texas, and south of the outflow cool pool, it appeared the best place to be would be anywhere from I-35 near Gainesville, and points east towards Hugo, Oklahoma (either side of the Red River). The SPC had this area in an enhanced risk, with tornado probabilities at 5%, and both wind and hail at 30% (the hail was hatched for significant). Heading east using Highway 82, I reached Gainesville and I-35, meeting up with Dan Shaw from Australia and watching storm initiation at a farmers ranch nearby. Dan and I would chase for the rest of this day by caravanning together. SPC issued MCD 541 and tornado watch 155 valid until 1 AM CDT the following day for this area as well. With initiation of a supercell storm to our NE, Dan and I headed north on I-35 to highways 32 and 70 east out of Marietta, OK. We followed highway 70 eastward to intercept the storm near Bennington. After chasing, Dan and I headed back west to SR 78 south for dinner near Bonham. I headed east on 82, and spent the night in Paris, Texas.

April 22 was an off day. I opted not to follow the storms eastward into Mississippi and Alabama, so I headed back west on Highway 82 out of Paris to Gainesville for late lunch, then south on I-35 to Denton, planning to spend the next couple of down days there. April 23 was an off day, and some time was spent at the Skydiving place northeast of McKinney (Skydive Spaceland Dallas) for a jump. April 24 I left Denton, Texas and headed north via I-35 to Oklahoma City, Oklahoma to be in position for anticipated activity in that area later in the week. April 24 I spent the night on the south side of Oklahoma City off I-35. The following day, April 25, was a chase day in north-central to northeastern Oklahoma. Upon forecasting and preparing my vehicle for resuming chasing, the best place to be for a marginal chance of supercells would be in the region extending from SE Kansas and points southwestward into Northeastern Oklahoma near and northwest of Tulsa.

Late in the morning on April 25 I headed north out of Oklahoma city via I-35 north to near Tonkawa, then started east on Highway 60 to Bartlesville. The storm prediction center upgraded the slight risk earlier to enhanced on their 1630z outlook, with a 5% tornado, 15% wind, and 30% hatched hail probability near the target area. MCD 553 and severe thunderstorm watch 159 were also issued, with the watch valid until 2 AM CDT the following day. Storm initiation began west of the target areas just east of I-35, but quickly tracked northeastward with some of the cells reaching my location near Fairfax and Hominy and was followed down via SR 20 and 18 towards Pawnee. The chase then turned back east to near Cleveland on Highway 64. The chase was wrapped up by heading south on Highway 75 to I-44 and checking out severe storms near Sapulpa to the southwest of Tulsa. I spent the night in that area as well when I was finished chasing for the day.

April 26 was a rather long and frustrating chase day, and left little to show for it. I hastily looked at data early, knowing I would need to go south and east out of Tulsa quickly, to make a target area to the east of Texarkana and into southern Arkansas. The SPC had this area in a moderate risk, with 15% hatched tornado (significant), 30% wind, and 30% hatched hail probabilities on both the 13z and 1630z outlooks. These were to later be reduced, and for good reason. I headed out of the Tulsa area, and down Highway 75 to Henryetta, taking the Indian Nation Turnpike (toll) out of there to Hugo, Oklahoma, then 271 south to Paris. I headed east on Highway 82 to near New Boston, then I-30 east into and through Texarkana, where I got ahead of an ongoing line of thunderstorms. Anticipating the broken line of storms to form into more discrete supercells, just the opposite happened. I realized that heading NE on I-30 towards Hope, Arkansas (losing "hope" for good storms at the same time)!

Realizing the severe event was going to be nothing more than a messy squall line (outflow dominant) and surging Pacific cold front, I headed south out of Hope on SR 32 and towards Willisville, then east to near Camden on Highway 278. I took 79 out of Camden then 371 to the SW out of Magnolia to head back west to near SR 359 north. The SPC also had MCD 560 and Tornado watch 162 valid until 5 PM CDT for this area and points northeastward. Ultimately, not a single tornado was reported anywhere in the USA with this setup during this time period! I headed back on SR 359 to Texarkana for dinner, then west on I-30 to Highway 380 into McKinney, Texas for the night. The following day, April 27, was taken as an off day with only marginal storm chances out of range in SW Kansas. I repositioned north towards Oklahoma City via Highway 75 north, then I-35 north into Norman, Oklahoma for the night on April 27. This was to get into position for the next, lonq-awaited, Pacific trough to affect the area the next few days.

April 28 was a typical "cap bust" day. The late arrival of upper air support left the area near and south of a warm front capped (stable mid level layer) until late at night. I pretty much hung around the area from near Norman, to Chickasha via SR 9 and Highway 277, then back southeast towards Pauls Valley on SR 19 to wait until late afternoon. I met with Jerry Prsha and his chase partner in Pauls Valley as well. SPC had a large area in enhanced risk, with 5% tornado, 15% wind, and 30% hatched hail in the outlooks stretching into my target area. A 10% tornado area was also progged by SPC father east over KY and TN, but also remained capped and was not realized. At around dusk, realizing no storms were going to develop during daylight, I decided to head west towards Lawton for the night, anticipating late storm development after dark there, as well as being in a good position for storm prospects the next day on the 29th. I headed down I-35 to SR 29 west, then SR 7 to Lawton. No additional storms developed until after midnight in that area (severe storms with damaging winds remained to the north during the early morning hours).

April 29 was a chase day with low expectations but wound up being a day to be remembered for a long time. Upon looking at data, the best place to be was well east of a surface low over south-central Oklahoma and ahead of a surging Pacific cold front. The SPC had a large area of Enhanced risk, with a 5% tornado, and 30% for both wind and hail in their probabilities. I chose a preliminary target area near Paris, Texas. I left Lawton via SR 7 east to 81 south through Duncan, then 70 eastward all the way to Hugo, Oklahoma. The low pressure area was crossed as well, with 30 MPH north winds and 50 deg F temps in Lawton, calm winds in Ardmore near Highway 70 and I-35 with temperatures in the mid 60's, then strong south winds near 30 MPH and temperatures in the 80's towards Hugo. I headed south on 271 out of Hugo to Paris, Texas. Looking at data, a large CAPE area was noted near I-20 and Mineola, along with a highly-sheared and weakening cap environment. The target was adjusted as such.

I headed down Highway 271 out of Paris, then SR 37 south and southwest towards the cumulus area noted on visible satellite. The SPC issued MCD 594, and eventually tornado watch box 175 valid until 10 PM CDT for the same target areas. I continued south and southwest on 37 towards Mineola, then west on Highway 80 to SR 19 south out of Fruitvale. By this time, three major supercell storms developed on the southern end of the storm cluster. South of Canton and near Eustace, two tornadoes were observed, one being a violent wedge tornado causing deaths and extensive damage from Canton to Fruitvale. I followed the storm from I-20 east, then back north via SR 110 and west on 80 but was blocked by the damage path. I concluded chasing and headed back east on 80 to backtrack NE to I-30 on SR 37. I headed through Texarkana and continued northeast into Arkansas. I was not able to find a place to stay (original stay was to be in Arkadelphia, but power was out there) for the night until Little Rock, Arkansas in torrential rains.

April 30 was a highly conditional chase day and started off by doing two interviews early in the morning for CNN and HLN for video I submitted the day prior. Chase prospects were over hyped for the day, but from my perspective appeared not very good for chasing, despite SPC having a large area in an enhanced risk over the mid south, with a 10% tornado, and 15% wind and hail in their probabilities. A 5% tornado and slight risk extended northward to the southern Great Lakes. With my chase bias being more northward as I planned to be near Chicago anyway the following days for downtime, I decided to head northward, anticipating any activity near the warm front and ahead of the low, and if not, still be near Chicago anyway late in the day. I headed out of Little Rock via I-40 east to west of Memphis, Tennessee, then I-55 north to the Missouri "boot heel" area. From there, I headed north on I-57 through Illinois, seeing little or no storm activity there by late afternoon. I continued north and reached the Chicago by late evening, and will spend a portion of the down-time over the next few days there at a friendís place.

The next period was down time and I took a break from storm chasing, spending time in Chicago and back in Florida to take care of business there and spend time with family and friends there until activity picks back up. I spent time in Chicago from April 30 to May 3, and flew down to Fort Lauderdale, Florida from Chicago on May 3, spending time there until May 8 (also attending the air show in Fort Lauderdale that weekend). On May 8, I flew back up to Chicago, and spent the night there, then began the long drive back out to Oklahoma on May 9, with storm activity also increasing those days. On May 9, I left Chicago early, heading down 53 to I-55, reaching Saint Louis by around lunch time. I passed west on I-64, then after a minor navigation mistake, back-tracked near Chesterfield to I-44 southwest through Springfield and into Oklahoma. I continued southwest along the I-44 (turnpike through Tulsa) and reached Oklahoma City by late evening, meeting up with Derek Sibley (from Mobile Alabama) near Will Rodgers Airport. He parked his vehicle, and we continued west on I-40 to near El Reno, to visit the Samaras memorial, and take dinner, and finally spent the night in Clinton, Oklahoma.

May 10 was a chase day with seemingly good chase prospects in SW Oklahoma and near and to the south of the eastern Texas Panhandle area. The SPC had this area in an enhanced risk, with a 10% tornado probability bulls eye over the area, plus a 15% wind and 30% (hatched for significant) hail probability. Derek and I forecasted during the morning, and a good starting point appeared near the Wellington / Childress / Matador area in Texas, which was pretty much a drive out of Oklahoma west on I-40 to highway 83 south out of Shamrock, Texas to the target area(s). Later on during the early afternoon, SPC issued MCD 684 and subsequent tornado watch box 204 near and around our target area, valid until 10 PM CDT. Convective initiation began just before 3 PM and near Matador, with a supercell forming there, and tracked NE as far as Altus, Oklahoma near Highways 287, 62, and route 6 back across the Red River through Quanah. Hail damage occurred with this storm to the vehicle hood as well as a small crack in the windshield. After abandoning that storm, we continued back south on Highway 283 and west of there in Texas near Odell. A supercell was tracked from there, and eastward on 287 to near Oklaunion, Texas and back north on 183 and into Oklahoma through Davidson to near Frederick, then east on 5 to near Chattanooga, then east to end the chase near I-35. We took highway 5 south and east to Highway 70 east, stopping in Waurika for dinner, and spending the night in Ardmore, Oklahoma.

May 11 was a marginal chase day tornado-wise, and the target was to be east and north of yesterdays, anywhere from near I-35 around Perry and points eastward to near Tulsa. SPC initially (13z outlook) had this area in a slight risk, with tornado probabilities of 2%, and 15% for both wind and hail (the hail was hatched). At the 1630z outlook, these were upgraded to an enhanced risk, with 5% tornado and 30% hail (hatched), and winds still at 15%. We forecasted and agreed on a target (near and south of Perry, OK and I-35) and with early initiation around 18z (1 PM CDT) and after. We headed up I-35 through Oklahoma City and reached the target area around 2 PM CDT, with areas of storms initiating, one that we chose being west of I-35 near Kingfisher. Meanwhile, the SPC issued MCD 694 and subsequent severe thunderstorm watch box for the same areas, valid until 9 PM CDT. We followed the storm from its contact near Crescent / Guthrie and Highway 77, to the east (after a rather frustrating fuel stop and Guthrie traffic) via east on SR 33 past Perkins and to Cushing. Very large hail, again, was encountered. Out of Cushing, we went north on 18 to 51 east through Yale. We went east on 51 to 48 north, then finally east on 64 to Tulsa after abandoning the storm (evolved a line segment at that point). We passed west of Tulsa, then to near Sapulpa, then back SW on route 66 to I-35 north of Oklahoma City. We spent the night in Oklahoma City.

May 12 was an off day, and the start of another short lull in storm chasing prospects, lasting at least few days. Derek decided to go back to Alabama that day to take care of work / school related stuff, but planning to return when storm prospects pick up again. I dropped him off near Will Rogers airport, and he picked up his car parked there for the drive back. I spend the rest of the day near I-35 in Oklahoma City, updating chase logs at the library there, and changing the oil in my vehicle. I spent the night in Norman, Oklahoma. On May 13, I traveled down to Texas via I-35 south and Highway 82 east to skydive near Whitewright to pass down time. Later that afternoon, I headed west on FM 121 to 377 then 380 spending the night in Denton, Texas.

May 14 was a re-positioning day to head west with no storm prospects expected, but a marginal risk panned out with some very photogenic marginally severe storms in the Caprock Canyon country near Amarillo. I forecasted a bit, and headed west on 380 to 287 through Wichita Falls, then eventually to near Amarillo. The SPC had a marginal risk for this area, with wind and hail probabilities at 5% (no tornado probability area). Convective initiation began near Amarillo around 2-3 PM CDT with the onset of heating and the dryline. SPC also issued MCD 714 for the area, but no subsequent watch areas as the severe threat was to remain isolated. I checked into my hotel on the east side of Amarillo at 3 PM, then headed out to go north on highway 87 / 287 to investigate high based convection near Dumas, then back down through Amarillo via 87 to I-24 to near Canyon for more storms, then east towards Wayside on FM 285 then SR 207 through the Palo Duro Canyon to Claude, then back to near Amarillo on 287, then east on I-40 and Highway 207 north to near Panhandle, Texas to check out another weakening supercell storm. I went back down to Highway 60 to Amarillo, spending the night there.

May 15 was a pretty good chase day, with storm prospects pretty much right over the Amarillo area, and northeastward into the Texas Panhandle area. The SPC had this area in one of three slight risk outlooks across the USA for the day, with hail and wind probabilities for the Texas Panhandle region both at 15%. There was no tornado outlook for this area, but since I was already there, and this area is noted for "surprises" (as you'll see later), why not chase it? I loitered around the west side of Amarillo after a late lunch off I-40 and SR 335, until the dryline and towering cumulus became evident overhead. By late afternoon SPC issued MCD 717, and subsequent severe thunderstorm watch box 213, valid until 10 PM CDT for the area. I headed out via SR 136 and chased the supercell storms from southeast of Dumas and to near Stinett on SR 152 and 207, and eventually near Spearman, ending the chase along Highway 83 to the NW of Canadian, Texas. A possible weak tornado was observed with the late stages of the storms looking NW from 83 towards Waka at roughly 9:15 PM! I continued generally eastward on Highway 83 to SR 33, then 183 to Clinton, then back east on I-40 to Oklahoma city to meet up again with Derek Sibley who drove back out earlier.

May 16 was a pretty busy, tiring, and frustrating chase day - However, still managed to catch the tornadoes. The SPC had the area in the eastern Texas Panhandle in a moderate risk, with 15% hatched (significant) tornado probabilities, and 45% hail (also significant). Wind probabilities were 15% for OUR area, with a 30% hatched area farther northeast well away from our targets. We woke up early and decided on a preliminary target area of near Canadian, Texas. Derek parked his car in Oklahoma City, and we headed west on I-40 in my vehicle. We headed NW on Highway 270, then eventually west to near Higgins and Shattuck. SPC issued MCD 730 and subsequent PDS (particularly dangerous scenario) tornado watch box 220 for this area, valid until 10 PM CDT. We crossed into Texas along Highway 60, then NW towards the first tornadic storm near Perryton, Texas near Highways 83 and 270. Being too far north of the beast environment for storms, we backed southward on 83 all the way to Wheeler, Texas where we encountered a deadly HP tornadic storm there, then eventually south to I-40, back east into Oklahoma, and came across the third violent supercell of the day near Erick, Oklahoma. Dropping south out of Erick, and east on 152, we encountered the Elk City tornado at close range. We followed this storm eastward and northward to near Thomas on SR 44 / I-40 after a frustrating fuel stop in Clinton (power out in many areas due to strong inflow). We wrapped up the chase and headed back to Clinton only to find power out at the hotel there, so we could not check in. Power outages and data issues along I-40 made getting a room for the night impossible. We headed east on I-40, stopping for dinner in El Reno, then spent the night on Oklahoma City - In the same hotel, and ironically the same room, as the previous night.

May 17 was an off day, with most storm chasing prospects distant in Iowa and Wisconsin, and not worth going up there - Especially with the forecast for May 18 looking to be another extremely busy day in western Oklahoma. We decided to keep the same hotel another night, and that day we headed west on I-40 back to Elk City for a damage survey from the tornado there a day earlier. We headed back on I-40 and spent the evening with Dan Shaw, Brett Adair, and several other storm chasing comrades at the TopGolf center on the north side of Oklahoma City for golf fun and dinner. We spent the night in Oklahoma City anticipating a moderate to high risk chase the following day on May 18.

We woke up to a high-risk chase day on May 18, expecting a major tornado outbreak in Oklahoma. By the end of the day, it turned out to be more or less mediocre day for chasing with more messy storm development instead of discrete supercells. We forecasted and left Oklahoma City during the morning and headed west to near El Reno on I-40, then Highway 270 to the preliminary target area of Woodward, Oklahoma, stopping there to look at data and for lunch. By 1630z, the SPC had much of NW Oklahoma and SW Kansas in a high-risk outlook. Tornado probabilities were 30%, wind at 30%, and hail at 45%, ALL hatched for significant. By early afternoon, SPC issued MCDs 756 and 758, and subsequent PDS (particularly dangerous scenario) tornado watch boxes 235 and 239 for the area, valid until 8 and 11 PM CDT, respectively. From early afternoon, it became apparent that convection was developing from south to north in a weakly capped environment, which is bad for a good chase. The result was a messy cluster of storms everywhere by late afternoon, with tornadic supercells embedded in areas with better air to work with, not the fearful long track violent tornadoes expected by many.

The chase took us out of Woodward to west of town near Fargo and Fort Supply, then north on 183 to 64 east out of Buffalo and to near Alva. Two tornadic supercells were encountered there, one rain wrapped near Alva, and another classic one with a tornado near Avard and NE of Waynoka off Highway 281. We backed up 281 to Alva and back west on 64 to SR 14, then south to reach 281 and all the way to Seiling, then continued south via 183 to near Custer City, and west on SR 33 to check convection near there. We wrapped up the chase via 33 back to 183 south to Clinton, meeting several other chasers (including Ben with Weather Nation and Tim Marshall) for dinner. I did an interview there as well for Weather Nation. After dinner, we spent the night in Clinton, Oklahoma.

May 19 was supposed to be sort of a "redemption" for some folks who failed on May 18, with a good area in SW Oklahoma. Upon waking up, we saw that overnight and morning convection severely complicated the forecast for the day. There were basically two targets: One in western to central Texas, and another a similar distance in south-central Kansas. Ultimately, the SPC had an enhanced risk out for the area, and a 5% tornado, 30% wind, and 30% hail in their probabilities on both their 13z and 1630z outlooks. We left Clinton via Highway 183 south back into Texas to near Oklaunion. Out of there, it was on 287 to Electra, then south and southeast on SR 25 to Archer City, then 79, 16, and 67 to near Breckenridge. Severe storms were encountered near Graham. By the afternoon, the SPC issued MCD 774 and subsequent tornado watch box 246, valid until 8 PM CDT for these areas. Supercells and line segments were the result southwest of Abilene near Ballinger. We continued west on 180 to 283 south to near Coleman, then west on 67. We headed south to near Voss on FM 503 and 1929 near the OH Ivie reservoir to intercept the storms there. We wrapped up heading west to 83 north to Abilene, then SR 351 NE to 180 near Acampo to stop and view some storms to the NW. We continued back east on 180 to 283 to 183 in Throckmorton, then east on 380 into Decatur, Texas, spending the night there.

The next day, May 20, was an off day with slight risk areas far away in south Texas or to the east near the Mississippi River, and a harbinger to a potential ridge and extended down time. We left Decatur during the late morning and headed back to I-35 north via FM 51. We headed to Oklahoma City and I dropped Derek off to pick up his vehicle as he was to begin the drive back to Mobile, Alabama the following day. This was an off day and I spent the night in Oklahoma City, anticipating a drive back west myself the following day for marginal setups farther west.

May 21 was mostly a travel day, but turned out to be an impromptu chase westward into New Mexico for a pretty good intercept of a supercell storm there south of Tucumcari. I headed out of Oklahoma City around lunch time, westward on I-40, reaching Amarillo by mid to late afternoon. I checked into the motel there early, as would need to be in this area for the next couple of days. Upon looking at some data, two areas of convection looked possible: One to the far north near the CO / OK border, and a closer area to the west in eastern New Mexico. The SPC had these areas in a marginal outlook, with no tornado probability, and wind and hail both at 5%. By late afternoon, MCD 808 was issued, but no watch area was required as per SPC. I headed west on I-40 after a late forecast and reached Tucumcari, New Mexico by early evening. Supercell storms were on going by that time, with an intense storm southwest of town near McAlister and House off SR 209 and 156. This storm may have produced a possible tornado (at least a rotating wall cloud with funnels)! After chasing I backed up SR 209 to SR 39 north, and back to I-40. I headed east to Amarillo by late evening (10:30 PM or so), and spent the night in Amarillo, Texas.

May 22 was a pretty good chase day with two supercell storms intercepted in eastern New Mexico mainly in Chaves County. I forecasted and found the best play for the day was the upslope convection in eastern New Mexico, throwing away the previous dayís target of Lubbock. The SPC had a slight risk area, stretching from eastern New Mexico into western Texas, with a 2% tornado, and 15% for both wind and hail for their probabilities as of 1630z. I headed out of Amarillo during the early afternoon via I-27 south to 70 west out of Plainview. I continued west on 70 to Roosevelt County, New Mexico. Supercells were intercepted there in the afternoon, with the chase heading down 70 to 285, then through Roswell and east on Highway 380. I wrapped up the chase meeting with Dan Shaw for photography. I continued east to near Tatum, then north on SR 206 back to Highway 70 near Portales. I continued to Clovis, taking Highway 60 out of Farwell, Texas northeast to Canyon, then finally north on I-27 back into Amarillo for the night.

May 23 and 24 were down days, with no storm activity across much of the central USA within reasonable chase distances. On May 23 I decided to head back to Oklahoma City for preventative vehicle maintenance. I headed east out of Amarillo on I-40 to Oklahoma City. I spent the night near Norman, Oklahoma south of there as well. On May 24, I decided to make my way north slowly, taking the scenic routes through rural Oklahoma west of Oklahoma City. I headed west out of Norman on Highway 62 to Anadarko and north on 281 to Binger, then west on 152 to SR 54 north, with a stop in Weatherford for lunch. I continued north on SR 54 to 58 through Canton. I connected with SR 8 north, then 11 east to Highway 132 north into Kansas, and continued northeastward along SR 2 / 42 into Wichita. I checked into the hotel there early off Highway 400 / 54, and finished some laundry and errands. I was anticipating a trip to NW Kansas or even eastern Colorado the next day for the very start of the next possible storm setup.

May 25 was both a repositioning day, and marginal chase day as well. The conditional target area was in far eastern Colorado, north of Burlington, where the SPC had a slight risk outlook. Hail and wind probabilities were both 15% on the 13z and 1630z outlooks, and later a 2% tornado probability was introduced after 20z. I forecasted and decided on the Burlington, Colorado target, and left Wichita during the mid morning via I-135 northward. Once past Salina, I headed west all the way past Dodge City and into Colorado near Burlington by afternoon. Storms pretty much developed on cue northwest of there, and two supercells were intercepted. One near Highways 385 and 36 from Yuma County, Colorado eastward along Highway 36 to Cheyenne County, Kansas. This first one produced large hail and a weak tornado. Continuing south and eventually east via SR 27 through Goodland to I-70, the second storm was encountered from near Oakley, Kansas and eastward to south of Wakeeney near Highway 283. After chasing these storms was completed, I back-tracked up 283 to I-70 west out of Wakeeney, spending the night in Goodland, Kansas.

May 26 was another chase day, also in Colorado and into Kansas, in pretty much the same areas as the day before, maybe starting out farther west. The SPC had an area over much of northeastern Colorado and in to part of western Kansas in a slight risk outlook, with hail and wind probabilities both at 15%, and a 2% probability of tornadoes. Upon forecasting, it appeared the best place to start out would be near the eastern side of the Palmer Divide area, anywhere from I-70 east of Denver towards Limon and Byers. I headed west on I-70, reaching Limon around lunch time, and waited for storms to organize on the higher terrain southwest of Byers off I-70. Storms eventually organized in the upslope airflow by mid afternoon, and a long-track supercell was followed from near Byers, and eastward along Highway 36 to near Idalia (again). The SPC also issued MCD 844 and subsequent severe thunderstorm watch box 268, valid until 8 PM MDT (9 PM CDT). The storm was followed east and southeastward, via 36 and 385 to Burlington, then back into Kansas on I-70 to east of Goodland. After chasing was wrapped up, I continued east on I-70, making the long drive to Salina, Kansas (to be in range for a busy chase day on the next day), arriving there for the night after midnight.

May 27 was yet another over-zealous moderate risk chase day with a target area east of I-35 into NE Oklahoma and SE Kansas, and had high expectations. The SPC had a large area in a moderate risk outlook, with wind and hail both at 45% (and both hatched for significant). The tornado probabilities were 10%, with a hatched area over NE Oklahoma and into SW Missouri. The plan of the day was to target an area east of I-35 in east-central to NE Oklahoma, with a primary target area near Osage County. This area was south of a front / outflow boundary, with a dryline forecasted to push east at the time of maximum heating, and with extreme instability. I forecasted and left Salina during the morning, heading down I-135 to Highway 81 south out of Wichita. I continued south to I-35 near Braman, Oklahoma and east on Highway 60, waiting in and around Ponca City in moist air more comparable to Miami (Florida) than Oklahoma (dewpoint in mid to upper 70's)! The area remained capped, and I hung around the area between Highways 60 and 64. SPC put out MCD 866, depicting late storm development due to capping. Tornado watch box 279 was issued for the area by 4 PM, valid until 12 AM CDT the following day. A subsequent MCD 873 was issued near time of initiation. At the end of the day, storms developed, went supercellular, then either got undercut or evolved into an MCS. No tornadoes were observed, again. A supercell with large hail was followed from Osage County near Pawhuska, and eastward to near Adair along Highway 60 and SR 66 before it weakened. I finished chasing, and headed southwest along SR 66 to Tulsa, spending the night there off I-44.

From May 28 onward, a rather lengthy period of less than ideal chase conditions prevailed, with a dreaded high pressure ridge building in the western USA and east coast trough as per forecasts. With that in mind, I decided to take at least a week break from chasing. I left Tulsa on the 28th during the late morning and headed up I-44 out of Oklahoma and across Missouri to 270 north of Saint Louis. I crossed into Illinois, and headed north on I-55 to Chicago, spending a couple of days there. I parked my vehicle in Chicago and flew down to Florida after the Memorial Day weekend to take care of some medical / dental stuff, as well as other needed issues there. With storm activity still slow across the Central USA, I stayed in Florida until June 5 and headed back to Chicago that day. I remained in the Chicago area, waiting out the remainder of this quiet period, until chasing and traveling resumed on June 11.

June 11 and 12 were the first travel and chase days, respectively, with the 12th being a major setup (with tornadoes intercepted) in the lee of the Rockies in the Nebraska, Wyoming, and South Dakota tri-state areas. I left Chicago early on June 11, heading out via I-88 and I-39 west and northward out of town and into Wisconsin. I took I-90 out of Madison, and headed west passing some marginally severe storms that day (SPC had an enhanced-risk over northern Wisconsin but it's difficult to chase there), and across southern Minnesota, reaching Sioux Falls, South Dakota by late afternoon, spending the night there. The next day, June 12, I continued westward on I-90, targeting a region anywhere from eastern Wyoming to NW Nebraska and SW SD. The SPC would eventually have a moderate risk, with 15% tornado (hatched for significant), 30% wind, and 45% hail (hatched) over an area in east-central to SE Wyoming as per their 1630z outlook. I continued to Murdo on I-90, then south on Highway 83 to 18 west to near Pine Ridge, then 87 south to Highway 20, taking that west into Wyoming near Lusk. The SPC issued MCD 995 and subsequent PDS (particularly dangerous situation) tornado watch box 317 for the area, valid until 8 PM MDT (9 PM CDT). I waited in Lusk and targeted the first tornadic supercell via Highway 85 south near Fort Laramie. After that, I took Highway 26 out of Torrington to SR 71 south out of Scottsbluff in Nebraska, ultimately intercepting another southern supercell and the last of many of its tornadoes near Harrisburg. I wrapped up the chase near dark by SR 88 near Bridgeport, meeting a few chasers there (including Charles Edwards). For the night, I headed southeast along Highway 26 to Ogallala, then I-80 east into North Platte, spending the night there.

June 13 was another significant chase day, although with less expectations of the day before, with my main target anywhere from east-central South Dakota, western Minnesota, and southward, if necessary, to SE SD and NE Nebraska. This involved a very long drive back east to the target area(s): One being just east of the ND / SD border in western Minnesota (warm front), and the other in SE South Dakota and NE Nebraska (dryline / pacific front). Ultimately I and most chasers chose the latter target. I left North Platte via Highway 83 north through Valentine, NE and into SD to near Mission, then east on Highway 18 to 183 north west of Winner, and then I-80 to head east from near Presho, SD. I continued east on I-80, reaching the target area by mid to late afternoon, and waited in the Mitchell / Salem area. The SPC had an enhanced risk outlook, with a large area of 5% tornado probability, and a 10% area in the western MN target area (this area also produced tornadoes later). There was also a 30% hail and wind probability, with the hail hatched for significant as per their 1630z outlook. MCD 1013 and tornado watch 323 were also issued, valid until 10 PM CDT. Two tornado-warned HP supercells were intercepted from near Kimball along SR 45 and Plankinton near Highway 281 and south / near I-80. These storms became outflow dominated, but produced brief / gustnado type tornadoes. I headed down SR 37 to near Avon and Tyndall, where the tail-end of the developing line of thunderstorms was encountered. I took SR 50 east to Highway 81 near Yankton, then into NE Nebraska along 81, then SR 12 / 15 south and east to Highway 20. A line segment producing destructive winds with trees blowing down was encountered near Bow Valley at dusk. Tree debris struck the vehicle, breaking the HAM radio antenna off. I continued south and east along Highway 20, spending the night in Sioux City on the Nebraska side. Power was out and I had to wait until power was restored to check into my hotel there for the night.

June 14 was a very marginal chase day with storms intercepted eventually in north-central to NE Missouri. The target area was on the southwestern side of some higher SPC probabilities in a large slight risk outlook. The wind and hail probabilities were both 15%, and an area of 2% tornado probabilities was included with the SW portion of that extending southwestward into Missouri. This was also in higher instability air not affected by overnight / morning convective overturning. I left Sioux City, Iowa and headed down I-29 for the long drive to the target area. By early afternoon, I reached Saint Joseph, Missouri and headed east on Highway 36 after stopping to pick up some supplies there. I headed east on 36 through Macon to the storms near Hunnewell and Emden in Monroe, Shelby, and Marion Counties and along SR Z. The SPC also had MCD 1026 and issued severe thunderstorm watch 329, valid until 8 PM CDT for the area. An HP supercell storm was observed in this area, which evolved to an intense line segment. After chasing, I headed south to Highway 24, taking that back west to near Wellington, then south out of there to I-70 via SR 131, and west on I-70 to stay in Blue Springs (east of Kansas City) for the night.

June 15 was another chase day, this time back into central Kansas for a severe MCS type setup. The SPC had much of central Kansas in a moderate risk outlook, with significant (hatched) hail and wind probabilities at 45% and 30%, respectively. In this area, only a 2% tornado probability was issued, due to expectations of the storms becoming outflow dominant very quickly. I got my vehicle serviced by late morning and began the journey west on I-70 through Kansas City and headed towards my target areas, which was near Hays and Russell in Kansas. Storms in this area began developing as early as 1:30 PM CDT, which was somewhat of a problem given I was still enroute. Meanwhile the SPC had MCD 1039, and eventually severe thunderstorm watch box 332 for this area, valid until 7 PM CDT. The target area was reached by roughly 3:30 PM CDT, with a tornado warned supercell storm observed west of Russell, Kansas thereafter. Another supercell storm was observed farther south near and west of 281, and near Lacrosse and eventually Pratt near Highway 56 and east of 183. I met up with Dan Shaw, and his chase partner Don Sanderson, and chased with them in the area, mainly reporting large hail via SpotterNetwork. After chasing, I wrapped up north of Pratt, Kansas on SR 61, then headed northeast on 61 to I-135 north out of McPherson. Incredible mammatus was observed north of Pratt. Dan Shaw was nice enough to give me a spare antenna to replace the one I lost on June 13. I headed north on I-135 to Salina, then I-70 west to spend the night in Topeka, Kansas, arriving there after midnight.

June 16 was a long and pretty interesting chase day, with powerful supercells intercepted in central Nebraska, with an extreme-damaging wind event followed from there back to northern Kansas! The SPC had an area of enhanced risk over the SW Iowa, SE Nebraska, NE Kansas, and NW Missouri regions. This included a 30% hail (significant and hatched), 30 % wind, and only a 2% tornado probability. By looking at data, the best bet was to choose a target area near Norfolk, Nebraska and points southeastward to near Lincoln. I left Topeka and headed north on Highway 75 into Nebraska. Near Lincoln, I headed west on Highway 6, then bumped north to 34 west through Seward and Aurora, then SR 14 north all the way to near Albion. The SPC issued MCD 1055 and then severe thunderstorm watch 339, valid until 10 PM CDT for much of the target area. Taking SR 91 east, then SR 32 north and east into Madison, the first tornadic (rain wrapped) supercell storm was encountered. Low on fuel, the chase continued south on Highway 81 to SR 91 east, then south on SR 15 to Schuylr for fuel. I continued west on Highway 30 to Columbus, then south on SR 69 back towards the west side of Lincoln. The storm complex was followed from there and many miles southeastwards. I continued south on SR 93B to Highway 6 east, then SR 15 south to SR 4 east towards Beatrice. Wind damage was found there, with many roads blocked by trees and powerlines. Finally, using Highway 77 south, I got ahead of the derecho producing severe MCS near Randolph, and back in Kansas. I continued south on 77 to Manhattan, Kansas, spending the night there.

June 17 was a final chase in a week long stint of chasing. Two good target areas were analyzed for this day, with one over central and eastern Kansas, and another one over northeastern Missouri and southeastern Iowa and western Illinois. The SPC had an enhanced risk outlook in place, with 30% wind and hail probabilities, both hatched for significant. Tornado probabilities were still at a low 2%. My plan was to choose the northeastern target area in NE Missouri, since I was going to head back towards Chicago anyway. I left Manhattan, Kansas via I-70 east through Topeka, and back into Missouri through Kansas City to the SR O near Odessa, and north to Highway 24 east. Near Hunnewell, I headed north on SR Z and eventually near Memphis on Highway 15, intercepting a supercell storm there. The SPC also had MCD 1071 and subsequent severe thunderstorm watch 345 valid until 1 AM CDT the following day from that area northeastward. After a short chase the storm continued southeast and downed trees blocked the roadway (Highway 136). Backtracking to SR A south and around the block, a downed tree also blocked that route, and I used the winch to clear the tree. I continued on back to Highway 136 east, and eventually Highways 61 and 34 north and east into Iowa and Illinois. I headed up Highway 67 and into Moline, Illinois, Spending the night there. The following day, June 18, I headed east on I-80 out of Moline to Peru, then north on I-39 to Rochelle, and east on I-88 to spend a few days in the Chicago area.

From June 18 through June 20, I was in the Chicago area, and planning the end of chasing, until a late season setup caught my eye, and I decided to throw in one more attempt at catching storms, mainly during the period from June 21st to the 22nd. I also had the choice of chasing a tropical storm near the northern Gulf region. With the latter being weak, sheared, and not worth it, I decided on the severe potential back out west. On June 21, this area seemed to be in the quad-state area where NE, SD, IA, and MN meet. On the 22nd, it was either farther east over Iowa, or west towards SW Nebraska / NE Colorado. On paper this looked good, but heading out in actuality proved to be a senseless waste of time and money at the end of the day! I left the Chicago area via I-88 west to I-80, and spent the night of June 20 in Des Moines, Iowa. During the morning of June 21, I headed west on I-80 out of Des Moines, then north on Highway 59 to near 18 west to the NW corner of Iowa. The SPC had a slight risk, with a 15% wind and hail (the latter hatched for significant), and a 5% tornado probability as per their 13z outlook.

By 1630z on June 21, the SPC removed the 5% tornado probability and it became apparent that this area was plagued by a capping inversion aloft. MCDs 1110 and 1113 were issued for far SW Nebraska and N Kansas and far North Dakota / W MN, respectively. By late afternoon some marginally severe storms developed in NE / KS, with a short lived tornado warned storm from Fargo and into MN along the warm front (looked good on radar but nothing reported by chasers in MN who were on it). I headed west on Highway 18 into S Dakota, then along I-29 near Sioux Falls. Nothing developed there, and it became apparent a "cap bust" was the result of over a 750 mile drive. Some small storms developed near and after dark in this area, but couldn't sustain themselves. I spend the night, in a very frustrated mood, in Sioux Falls, SD - Watching tornado reports from Florida to Mississippi from the weak tropical storm in the Gulf of Mexico.

June 22 I was discouraged and not willing to storm chase in the central USA for season 2017. I agreed to just head back to Chicago (before making the final drive back to S Florida). I headed east on I-90 out of Sioux Falls, SD and into Minnesota to I-35 south out of Albert Lea. I continued south and east off I-35 to Highway 65 south around Mason City via SR 9 and CR S56 to Highway 18 east. I took Highway 218 southeast out of Charles City to Cedar Falls / Waterloo, then I-380 out of there to Cedar Rapids to take Highway 30 east. The SPC had a large slight risk area extending from Illinois to Colorado, with 15% wind and hail probabilities, and NO tornado probability (outside the 5% along the Gulf coast with TS "Cindy" making landfall west of there). At the end of the day, linear and weak convection formed over Iowa, with some brief small supercells eventually forming after dark. Meanwhile, I continued east and southeast across the front, picking up Highway 30 east, and crossing back into IL across the Mississippi river near Clinton, Iowa. Avoiding most of the I-88 tolls, I continued east on Highway 30 to near Aurora, then I-88 into the Chicago suburbs. I would spend time there from June 22 to early morning June 25.

On June 25, I left Chicago via I-88 to I-80, and I-65 southward through Indianapolis to I-24 east through Nashville, Tennessee. I headed east on I-24 then I-75, spending the night in Marietta, Georgia on June 25. Using I-75, I headed south on I-75 through Atlanta, then past Gainesville, Florida to Ocala, Florida. From there I took the FL Turnpike SE through Orlando to I-95 near Fort Pierce. The final leg was via I-95 southward through Palm Beach County, and into Deerfield Beach by around 10 PM on June 26. This wrapped up this very long chase trip, and the total mileage on the vehicle since April 17 was 23,701 miles.


CHASE EXPEDITION 2017 MAIN PARTICIPANTS

CHASER NAMEHOME / BASE CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURADEERFIELD BEACH, FLKG4PJN4-17 TO 6-26IT CONSULTANT
DEREK SIBLEYMOBILE, ALN/A5-9 TO 5-20STUDENT


DETAILED CHASE LOG FOR CHASE EXPEDITION 2017

1). April 19, 5:15 PM - Interception and indirect penetration of a very severe, and possibly tornadic thunderstorm in Cass County, Nebraska to the southeast of Lincoln, and near Eagle along Highway 34. The storm was a classic supercell storm developing in a line segment of strong and severe storms. A large area of rotation, and possible tornado was noted looking west and approaching the storm from the east. The storm weakened but a rotating wall cloud was noted near Manley along SR 1. The core of this storm was not directly penetrated, but had hail up to 2". Penny sized hail, 50 MPH winds, heavy rains, and occasional lightning was noted during my encounter with this storm. Conditions causing the storm were a Pacific front (overtaking a dryline), low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 10 PM CDT.

2). April 19, 7:30 PM - Interception and indirect penetration of a severe thunderstorm from Otoe County, Nebraska along Highway 75 and SR 2 and eastward into Fremont and Page Counties, Iowa towards Bedford. The storm was a small HP supercell embedded in a line segment. A wall cloud and hail core was observed with this storm before it became outflow dominant and weakened into a line segment. The core was not directly penetrated. Lightning, heavy rains, small hail, and 50 MPH winds were encountered. Conditions causing the storm were a Pacific cold front, low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 10 PM CDT.

3). April 20, 10:30 PM - Interception, observation, and indirect penetration of a very severe thunderstorm to the northwest of Vernon, Texas and southwest of Altus, Oklahoma near and south of the Red River along Highway 283, mainly in Wilbarger County, Texas. The storm was one of a few intense elevated supercell storms (north of a stationary front to the south). The core of this storm was not directly penetrated, but contained hail to tennis ball sized (with vertically-integrated liquid / VIL of ~80)! Penny sized hail, heavy rains, 50 MPH winds, and frequent (nearly continuous) lightning with many close hits was encountered with this storm. The storm also had a striking visual appearance (lightning illuminated) with "stacked plates" when viewed from the east. Conditions causing the storm were a stationary front, low pressure trough, upper trough, and intensifying low level jet. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was valid for the area until 5 AM CDT the following day.

4). April 21, 9:00 AM - Observation of a severe thunderstorm in Lawton, Oklahoma in Comanche County near I-44 and SR 7 from a stationary location. The storm was the southern end of a line segment of severe thunderstorms. The storm gust front struck; with winds gusting over 60 MPH. Sporadic lightning and heavy rain was also observed after the passage of the gust front surge. Blowing dust and some light debris was noted blowing around. Conditions causing the storms were a low pressure trough, surging outflow boundary, upper trough, and low level jet. A 2016 Jeep Wrangler was used to observe the storms. Documentation was audio and HD video. A severe thunderstorm watch was valid for the area until 12 PM CDT the following day.

5). April 21, 7:00 PM - Interception and observation of a very severe thunderstorm from near Durant, Oklahoma and eastward on Highway 70 to the west of Hugo and near Bennington in Bryan County. The storm was a classic supercell storm, which evolved to HP and later down-scaled to a weak line-segment at dusk. The storm core was not penetrated but probably contained very large hail. A large wall cloud and funnels were also observed with the inflow region of this supercell. The storm also had sporadic lightning and a striking visual appearance ("stacked-plates"). Conditions causing the storm were a prefrontal wave, Pacific cold front, low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 1 AM CDT the following day.

6). April 25, 7:30 PM - Interception and observation of severe thunderstorms from near Burbank to Pawnee in Pawnee County, Oklahoma along Highway 64 and points eastward. The storm started out as a small supercell strong storm, which back-built and evolved into a storm cluster, with an embedded HP supercell. The mail hail core was not penetrated (contained hail to golfball sized). Small hail, 60 MPH winds, very heavy rains, and frequent lightning was observed with this storm. A wall cloud was also noted, but quickly occluded as the storm weakened. Conditions causing the storm were a Pacific cold front, low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was valid for the area until 2 AM CDT the following day.

7). April 25, 10:00 PM - Interception and observation of severe thunderstorms to the southwest of Tulsa, Oklahoma near I-44 and Sapulpa in Creek County. The storm was an HP supercell storm that was on the southern end of a line segment of severe thunderstorms. The storm quickly evolved to a cluster of strong and severe storms. The core was not directly penetrated. Frequent lightning and heavy rains were observed. Small hail (pea to dime sized) and 50 MPH winds were also encountered at a stationary location near Sapulpa. Conditions causing the storm were a Pacific cold front, low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was valid for the area until 2 AM CDT the following day.

8). April 26, 4:00 PM - Observation of severe thunderstorms from east and southeast of Texarkana mainly in Lafayette and Columbia Counties in Arkansas, from near I-30 and southward to near Highways 82 and 371. The storms were part of a line of strong and marginally severe storms. Heavy rains, 50 MPH winds, sporadic lightning, and small hail were encountered in some of these areas. Conditions causing the storm were a Pacific cold front, low pressure trough, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A severe thunderstorm watch was valid for the area until 5 PM CDT.

9). April 29, 6:00 PM - Interception and penetration of an extremely severe and violent tornadic thunderstorm in Van Zandt County, Texas between Eustace and Tundra and west of SR 19 and southeast of Mabank. The storm was an HP supercell storm, the middle one in a cluster of three supercells. A brief view of a multivortex tornado was noted looking southwest as the storm occluded, meanwhile a stronger violent tornado was on-going to the WNW (rated EF-4). A brief glimpse of the edge of the EF-4 tornado (that tracked from Eustace to the west of Canton) was noted barely visible through the rain and hail. The core was not directly penetrated, but hail to golfball sized was observed with 65 MPH winds and torrential rains. The storm also produced frequent lightning with some close hits. The tornado quickly became obscured in rain and damage was mainly to trees. Conditions causing the storm were a prefrontal convergence ahead of a Pacific cold front, low pressure area, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 10 PM CDT.

10). April 29, 6:30 PM - Interception and observation of an extremely severe and violent tornadic thunderstorm in Van Zandt County, Texas from near Tundra along SR 19 and north ands east into Canton and eventually Fruitvale. The storm was violent classic supercell storm, and was the southern storm in a cluster of tornadic supercells. The storm produced a highly visible and well documented wedge tornado just east of SR 19 and northward across I-20. The storm also had a striking visual appearance. The tornado hit parts of Canton and Fruitvale, Texas causing deaths and destruction (probably EF-3 or higher damage). Many homes and businesses, including a car dealership, were completely destroyed. Cars also mangled and flipped. High tension transmission lines were also downed by the tornado with a very loud roar noted. The wedge tornado was 1/2 a mile, and maybe as wide as a mile. Frequent lightning with close hits, isolated hail to golfball sized, torrential rains, and winds gusting over 70 MPH (RFD) were also encountered with this storm. Conditions causing the storm were a prefrontal convergence ahead of a Pacific cold front, low pressure area, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was valid for the area until 10 PM CDT.

11). May 10, 4:30 PM - Interception and direct penetration of a very severe (and briefly tornadic) thunderstorm from north of Matador, Texas on ranch road 94 in Motley County and north and eastward through Childress County along Highways 62 and 287 east-southeastward to near Quanah, then north and northeastward on Highway 6 to near Altus in Jackson County, Oklahoma. The storm was a classic to HP supercell storm. There was a report of a weak / brief tornado on this storm west of Baker, Texas. The possible tornado was not observed. Passage was done through the storm core and "hook". Hail up to tennis ball sized (2.25") was encountered, with most stones 2". An isolated stone to 3" (baseball sized was seen smashing into the roadway). 60 to 65 MPH winds, torrential rains, and frequent lightning were also observed with this storm. Once east of the storm, a large RFD clear slot, rotating wall cloud, and striking ("stacked plates") visual appearance was noted looking WNW at the supercell. The hail guards were installed for this chase on the Jeep. No windows were lost. The hood was severely dinged by the larger hail-strikes. A small crack was noted in the windshield from a stone that bounced off the roadway. Other vehicles were severely damaged by the hail. Trees had some leaves shredded. Some trees and signs were blown down, and power knocked out. Severe flooding was observed near Altus, Oklahoma, as the supercell storm evolved into a complicated MCS of severe thunderstorms. Conditions causing the storm were a dryline, stationary frontal boundary, low pressure area, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills, audio, and HD video. A tornado watch was valid for the area until 10 PM CDT.

12). May 10, 7:00 PM - Interception and penetration of a very severe (and also briefly tornadic) thunderstorm from near Odell and Chillicoth in Wilbarger county, Texas west of Highway 283, then back towards 287 to near Oklaunion, Texas then north on Highway 183 through Davidson and Frederick in Tillman county, Oklahoma then east on SR 5 to near Chattanooga. The storm began as an LP supercell storm southwest of Odell, Texas, and evolved to a classic supercell, then eventually undergone up-scale evolution to an HP storm, and finally a line segment / large MCS after dark. A possible weak and dusty tornado was observed near and north of Davidson, Oklahoma while along 183 south of Frederick. The storm also contained hail to 2", winds gusting near 70 MPH, torrential rains, and frequent lightning (with some close hits). The storm had a striking visual appearance, especially during its early stages. The storm also had a pronounced RFD clear slot and wall cloud before becoming outflow dominated later in its life cycle. Conditions causing the storm were a dryline, stationary frontal boundary, low pressure area, upper trough, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills, and HD video. A tornado watch was valid for the area until 10 PM CDT.

13). May 11, 3:30 PM - Interception and direct penetration of a very severe (and briefly tornadic) thunderstorm from east of Kingfisher, Oklahoma in Logan County and Highway 77, and eastward through Guthrie and Perkins along SR 33 in Payne County, then to Cushing and west of Tulsa in Pawnee County and near Highway 64. The storm was an HP supercell storm that ended as a complex line segment by the end of the period (late afternoon) near Tulsa. A very brief tornado / gustnado occurred with this storm near Perkins, then later after we abandoned the storm well to the northeast of Tulsa near Owasso. The tornadoes were not observed. A spectacular gust front / shelf cloud (as well as undercut RFD cut and wall cloud) were observed with the storm during HP to bow-segment evolution. Extremely large hail was encountered in the core of the HP supercell, with some stones noted to 2.25" (tennis ball sized) and hail drifting from smaller stones on the roadside. The storm also backed winds exceeding 70 MPH, lightning, and violent rain. Conditions causing the storm were a dryline / Pacific front, stationary frontal boundary, low pressure area, upper level low, and surface heating. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills, audio, and HD video. A severe thunderstorm watch was valid for the area until 9 PM CDT.

14). May 11, 7:30 PM - Observation of a strong thunderstorm near I-35 and on the south side of Oklahoma City in Oklahoma County, Oklahoma. The storm was a small elevated LP supercell storm in a small line segment of strong thunderstorms. The storm contained small hail, light to moderate rain, 30 MPH winds, and occasional lightning. The storm had a very striking visual appearance (with striations and a "stacked plates" presentation) when viewed from the ENE. Conditions causing the storm were very cold air aloft, associated with an upper-level low, surface heating, and post-frontal (elevated) forcing in the mid-levels. The storm developed over an area of cool temperatures and winds from the NW. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A severe thunderstorm watch was valid for the area until 9 PM CDT.

15). May 14, 4:30 PM - Observation of a strong to marginally severe thunderstorm in Potter County, Texas along Highway 87 / 287 between Dumas and Amarillo. The storm was a marginal supercell storm with a high base that evolved to a line segment. The storm produced light to moderate rain, occasional lightning, small hail, and winds gusting near 60 MPH (mainly in small microbursts). Conditions causing the storm were surface heating, upslope wind flow, a lee surface trough, and a dryline. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills.

16). May 14, 6:30 PM - Observation of strong to severe thunderstorms from near I-24 in Potter County, Texas eastward to Armstrong County through the Palo Duro Canyon near Wayside and SR 207 northward to near Claude. The storm was a cluster of strong and severe thunderstorms. The storms were also high based, and produced light to moderate rain, frequent lightning, and winds gusting near 60 MPH. The core of the storm was not penetrated directly, and a large hail shaft was visible over the canyon back-drop. A small high-based funnel was also observed with a cell that aqcuired LP characteristics near Claude. Conditions causing the storm were surface heating, upslope wind flow, a lee surface trough, and a dryline. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills.

17). May 15, 6:30 PM - Interception and observation of a very severe, and later possibly tornadic thunderstorm from near Stinnet in Hutchinson County, Texas and northeastward towards Spearman in Hansford and Ochiltree Counties along SR 207 and eventually from near Highway 83. The storm was a classic supercell storm, and a large funnel cloud / possible tornado was observed late in the storms life cycle at roughly 9:15 PM looking NW from Highway 83 towards Waka, Texas. The storm had a very striking visual appearance during its mature stages, with a "stacked plates" appearance, and impressive RFD clear slot as well. Hail up to 2" was also noted on the side of the road behind the storm core, which was not directly penetrated. Torrential rains, 60 MPH winds, and frequent lightning were also observed with this storm. Conditions causing the storm were surface heating, a dryline, a surface trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 10 PM CDT.

18). May 16, 3:30 PM - Interception and observation of a very severe and possibly tornadic thunderstorm from near Perryton in Ochiltree County, Texas and northeastward into Beaver County, Oklahoma along Highways 83 and 270. The storm was a classic supercell storm with a possible tornado observed during its early life to the northwest of Perryton, Texas. The storm produced another funnel cloud and evolved to HP mode as it entered Beaver County, Oklahoma. The core of the storm was not penetrated, but likely contained large hail and strong winds. The storm had a striking visual appearance as well, with wall cloud and RFD cut. The storm eventually evolved to a line segment and weakened after 4:30 PM. Conditions causing the storm were surface heating, a dryline / Pacific front interactions, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 10 PM CDT.

19). May 16, 5:30 PM - Interception, penetration and observation of an extremely severe and tornadic thunderstorm from near Wheeler, Texas in Wheeler County along Highway 83 and south to near Twitty. The storm was an HP supercell with a powerful rain wrapped tornado, and a wide (1/2 mile or so) damage path was observed along Highway 83 south of Wheeler and north of Twitty. Power poles and lines were snapped and across the road, with some debris scattered (roofing material and trees). When the storm was penetrated from the north, rapidly shifting winds (north to west) were noted on the south side of Wheeler with winds approaching 75 MPH. Dime to isolated quarter sized hail, torrential rains, and frequent lightning was also observed. The tornado was rain wrapped and despite being close to our location, not visible. One person was killed in this storm. This was the same supercell and tornado that produced the more visible tornado near McLean, Texas earlier during its classic phase. Conditions causing the storm were surface heating, a dryline, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 10 PM CDT.

20). May 16, 7:00 PM - Interception, penetration and observation of an extremely severe and potentially violent tornadic thunderstorm from the southwest of Elk City, Oklahoma and southeast of Erick in Becklham County and northeastward to near Thomas in Custer County along SR 152, I-40, and eventually near Highway 183. The storm was an extremely severe HP supercell storm, and produced a large and destructive tornado that caused one death and damage in Elk City, Oklahoma. We approached the storm from the west, and eventually the western circulation of the tornado itself, passing through the intense supercell core and hook region. Extremely heavy rains, and copious amounts of 2" hail, with isolated baseball and even softball sized hail smashing / bouncing across the road - With the alarming silhouette of the developing wedge tornado in front of us on SR 152! The storm also contained frequent lightning (with some close hits). Winds in this area gusted over 100 MPH, especially in rear inflow jets / RFD on the backside of the tornado. A roof and debris (from a steel building disintegrating) was observed airborne off 152 with violently shifting winds as the tornado was highly rain wrapped. Damage in Elk City also was extensive, and debris was noted falling from the sky in RFD winds southeast of there near I-40. The storm continued to the NE into Custer County, Oklahoma and weakened / evolved to a line / bow segment near dusk. Conditions causing the storm were surface heating, a dryline, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 10 PM CDT.

21). May 18, 3:00 PM - Interception and observation of a very severe thunderstorm from near Fargo, Oklahoma to Fort Supply in Harper County, and along SR 46 to Highways 64 and 183. The storm was a classic to HP supercell thunderstorm. A rotating wall cloud was observed with this storm, but it quickly evolved to a line segment and weakened due to storms developing south and southeast of it. Conditions encountered were heavy rains, frequent lightning, 60 MPH winds, and small hail. The main core was not penetrated. Conditions causing the storm were surface heating, a dryline, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 8 PM CDT.

22). May 18, 4:30 PM - Interception and penetration of a very severe and tornadic thunderstorm in Woods County, Oklahoma near Camp Houston along Highway 64. The storm was an HP supercell storm with a possible rain-wrapped tornado in progress as it was penetrated from the west. A funnel cloud developing and disappearing into rain was observed, with an area of strong rotation / dust being lofted as the weak tornado developed and lifted north (in poor visibility). Hail to 1", strong winds to 60 MPH, very heavy rains, and frequent lightning was also observed when penetrating this storm. Conditions causing the storm were surface heating, a dryline, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 8 PM CDT.

23). May 18, 5:15 PM - Interception and observation of an extremely severe and tornadic thunderstorm in Woods County, Oklahoma along Highway 281 and between Avard and Waynoka. The storm was a classic and cyclic supercell storm. A large cone (or even wedge tornado) was observed with this supercell looking southwest from near Avard. The tornado evolved to multi-vortex and then a large wall cloud. Another wall cloud and large funnels developed as the storm cycled. The funnel formed from the new mesocyclone while the tornado near Waynoka was still in progress. The storm also had a very striking visual appearance (with "stacked plates" presentation). This supercell evolved to LP through downscale growth and weakened northwest of Alva. The storm core was not penetrated (contained at least 2" hail), but light rains, 40 MPH winds (inflow), and frequent lightning was observed. Conditions causing the storm were surface heating, a dryline, boundary interactions, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 8 PM CDT.

24). May 18, 6:30 PM - Interception and observation of a severe thunderstorms from west of Custer City and near highway 183 and SR 33 west of Putnam and Arapaho in Dewey and Custer Counties. The storm was a multicell cluster of strong and severe storms, formed by two supercells evolving to HP and merging ahead of the dryline. A large funnel was observed on the forward flank of the storms west of Putnam, as well as a large shelf cloud towards the southern portion of the storm complex. The cores were not penetrated. Frequent lightning, heavy rains, and 45 MPH winds were encountered. Conditions causing the storm were surface heating, a dryline, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A PDS (particularly dangerous scenario) tornado watch was also in effect for the area until 8 PM CDT.

25). May 19, 1:00 PM - Observation of a very severe thunderstorm near Graham and Archer City, Texas in Archer County and along Highway 79. The storm was an elevated supercell storm at the end of a line segment of strong and severe thunderstorms. The supercell storm was HP in nature, but still north of a boundary separating rain cooled air from earlier storms to its north. The storm had an impressive shelf cloud associated with its gust front. The core (containing golfball sized hail) was not penetrated. Frequent lightning, 40 MPH winds, and light rain were encountered passing the storm. Conditions causing the storm were surface heating, outflow boundaries, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A tornado watch was also in effect for the area until 8 PM CDT.

26). May 19, 6:30 PM - Interception, observation, and penetration of a very severe thunderstorm west of Voss, Texas and near the CH Ivie Reservoir in Concho County and east of Highway 83. The storm was and HP supercell and part of a cluster of strong and severe thunderstorms. The storms were outflow dominant. A rotating wall cloud was also observed before the storm got undercut. The core was not directly penetrated, which contained hail at least 2". Frequent lightning (with some close hits), heavy rains, 60 MPH winds, and small hail was encountered with this storm. Conditions causing the storm were surface heating, outflow boundaries, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A tornado watch was also in effect for the area until 8 PM CDT.

27). May 21, 6:30 PM - Interception and observation a very severe (and possibly tornadic) thunderstorm near McAlister and House in Quay County, New Mexico near SR 206 and 156. The storm was a classic supercell storm, and several large lowerings were observed on its southern side. The storm had a large rotating wall cloud, and several funnels, one of which might have touched down as a weak tornado. The storm core (with hail at least 2") was not penetrated, and the storm was viewed from the east. Frequent lightning, light to moderate rain, and 30 MPH winds was encountered east of the storm and away from the core. The storm was over rural areas. Conditions causing the storm were surface heating, upslope wind flow, a stationary boundary, a low pressure trough, and upper trough (NW flow aloft). A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills.

28). May 22, 5:00 PM - Interception and observation a strong thunderstorm over rural areas of Roosevelt County, New Mexico and west of Highway 70 near Delphos and Portales. The storm was a small LP supercell. Conditions encountered were occasional lightning, light rains, 30 MPH winds, and hail up to penny sized. One CG lightning bolt started a grass fire in an open field after it hit. Conditions causing the storm were surface heating, upslope wind flow, a stationary boundary, a low pressure trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A severe thunderstorm watch was in effect for the area until 8 PM MDT.

29). May 22, 7:00 PM - Interception and observation a very severe thunderstorm from west of Delphos and Kenna, New Mexico in Chaves County along and near Highways 70 and 285, and ultimately eastward along Highway 380 east of Roswell. The storm was an intense LP to classic supercell storm. The storm had a very striking visual appearance during all stages of its lifecycle, including RFD, hail shafts, rock-hard updraft, and rotating high-based wall clouds. The core of the storm was not penetrated, but contained large hail to at least 2". Copious amounts of quarter sized hail was noted along Highway 380 behind the storm. Other conditions were winds over 50 MPH (with dust), light rain, and frequent lightning. Conditions causing the storm were surface heating, upslope wind flow, a stationary boundary, a low pressure trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A severe thunderstorm watch was in effect for the area until 8 PM MDT.

30). May 25, 3:30 PM - Interception and penetration of a very severe and tornadic thunderstorm from Yuma County, Colorado eastward to near Saint Frances, Kansas along Highway 36 and near Highway 385. The storm was a powerful classic to HP supercell storm. The storm core contained hail to baseball sized. Hail up to golfball sized was observed in the hook of the storm near the intersection of Highways 385 and 36. Much of this hail accumulated on the ground do a depth of a few inches. A weak tornado was observed looking eastward from Highway 385 to the northwest of Hale / Bonny Reservoir and east of Idalia. The tornado was weak, lasted roughly 5 minutes, and remained over an open field. A rotating wall cloud was observed exiting the storm core to the northeast later. The storm also contained 65 MPH winds, torrential rains, and frequent lightning. The storm also had a striking visual appearance, with the base resembling a "cinnamon roll" and the weak tornado under it. Conditions causing the storm were surface heating, upslope wind flow, a stationary boundary, a low pressure lee trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was in effect for the area until 9 PM MDT (10 PM CDT).

31). May 25, 6:30 PM - Interception and penetration of a very severe and possibly tornadic thunderstorm from near Colby, Kansas along I-70 and southeastward to near Trego Center south of Wakeeney near Highway 283 in Gove and Trego Counties. The storm was an HP supercell storm. A possible tornado occurred with this storm near Oakley, but was rain wrapped and not visible. Strong winds gusting over 80 MPH were encountered east of Oakley on I-70. Torrential rains, quarter sized hail, and frequent lightning with close hits was also observed. Power poles were snapped and some structural damage occurred near Oakley. Flying tree debris was also noted blowing across I-70. Once east of the storm, before being undercut by outflow, the storm had a striated inflow appearance and large wall cloud with RFD clear slot on its southern side before weakening. Conditions causing the storm were surface heating, upslope wind flow, boundary interactions, a low pressure lee trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was in effect for the area until 10 PM CDT.

32). May 26, 5:30 PM - Observation and penetration of a very severe and possibly tornadic thunderstorm from Arapahoe county near Byers, Colorado via I-70 and Highway 36, then eastward through Washington and Yuma Counties to near Idalia, then eventually (via Highways 36, 385, and I-70) into Kansas near Goodland in Sherman County. The storm was a classic to HP supercell storm. Several penetrations were made on the storm, including a hook slice into the "bearís cage" north of Anton, Colorado. Very large hail, with numerous 2" (and possibly to tennis ball sized) was encountered with this storm. Heavy rains, 60 MPH winds, and frequent lightning were also encountered. A possible tornado was reported near Idalia, but it was low contrast and not visible from my vantage point. The storm had a very striking visual appearance, with striations, RFD cut with funnels, and dramatic "stacked plates" appearance. Conditions causing the storm were surface heating, upslope wind flow, boundary interactions, a low pressure lee trough, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was in effect for the area until 8 PM MDT (9 PM CDT).

33). May 27, 7:00 PM - Observation and penetration of a very severe and thunderstorm from near Pawhuska in Osage County, Oklahoma, eastward along Highway 60 through Nowata and Washington County to near Adair. The storm was a classic supercell that evolved to HP, then weakened to a line segment. A wall cloud was observed with the storm early in its life, with a striated "barber pole" updraft. Hail to 2" was encountered while going through the core of the storm near Nowata. The storm also contained frequent lightning (with some close hits), heavy rains, and 50 MPH winds were also encountered. Conditions causing the storm were surface heating, upslope wind flow, dryline / boundary interactions, a low pressure area, and upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was in effect for the area until 12 AM CDT (the following day).

34). June 12, 4:00 PM - Interception, indirect penetration, and observation of an extremely severe and tornadic thunderstorm in Goshen County, Wyoming near Fort Laramie, along Highways 26 and 85. The storm was a classic to HP cyclic supercell storm. A large rotating wall cloud and striking visual appearance was observed with this supercell, along with a few tornadoes (one a significant stove-pipe type) observed west of Highway 85. The tornadoes were not highly visible. The storm also contained grapefruit sized hail, frequent lightning, heavy rains, and 60 MPH winds. The core was not directly penetrated, and hail to golfball sized was encountered near Fort Laramie. Little damage was noted as the storm remained over open country. Conditions causing the storm were upslope wind flow, a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous situation) tornado watch was also in effect for the area until 8 PM MDT (9 PM CDT).

35). June 12, 6:30 PM - Interception, indirect penetration, and observation of an extremely severe and tornadic thunderstorm in Banner County, Nebraska near Harrisburg, along SR 71 south and SR 88 east. The storm was a cyclic supercell storm that had a long history of producing significant tornadoes (along a swath from NE Colorado and into Nebraska). The final tornado this storm produced was observed while heading south on SR 71 north of Harrisburg. The storm evolved to HP mode after this, with an impressive visual appearance. The core was indirectly penetrated, and quarter sized hail, 60 MPH wind gusts, heavy rain, and frequent lightning was encountered. The storm contained grapefruit sized hail in its core earlier, and one of the tornadoes destroyed a house. Conditions causing the storm were upslope wind flow, a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A PDS (particularly dangerous situation) tornado watch was also in effect for the area until 8 PM MDT (9 PM CDT).

36). June 13, 5:00 PM - Interception and penetration of a very severe and tornadic thunderstorm southwest of Plankington, South Dakota in Aurora County, and from near CR 23 to I-90 and near 281 to the north and east. The storm was an HP supercell storm. A large gustnado was observed with this storm as it was near I-90 and before it became outflow dominant. Strong winds to 60 MPH, frequent lightning, quarter sized hail, and heavy rains were also encountered with this storm. Conditions causing the storm were a dryline / Pacific cold front, a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was also in effect for the area until 10 PM CDT.

37). June 13, 5:30 PM - Interception and penetration of a very severe and possibly tornadic thunderstorm from near Stickney, South Dakota in Aurora County to Davison County and near Mitchell, and from Highway 281 to SR 37 via I-90 east. The storm was an intense HP supercell storm with very strong rotation as it was being undercut (again) by outflow. A rotating area with tagging rain curtains was observed near Stickney. The storm also contained quarter sized hail, frequent lightning, 65 MPH winds, and torrential rains. The storm evolved to a line segment, and this was followed as far south as Alexandria near SR 25. Conditions causing the storm were a dryline / Pacific cold front, a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A tornado watch was also in effect for the area until 10 PM CDT.

38). June 13, 8:30 PM - Penetration of a very severe thunderstorm from near Bow Valley, Nebraska in Cedar County, along SR 57. The storm was a line segment of strong and severe thunderstorms. An intense portion of the line was penetrated when back-tracking due to road construction and the area coned off by SR 12. Extremely heavy rains, frequent lightning, heavy and thick hail to 1" (quarter sized) covering the ground, and winds gusting over 70 MPH. Trees were downed along side the vehicle, with a portion of the tree striking the vehicle and breaking off the HAM radio antenna. The storm caused tree damage and power out in many areas as it continued southeastward through Sioux City. This made finding a hotel there very difficult due to wind damage. Conditions causing the storms were a dryline / Pacific cold front, a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 1 AM CDT the following day.

39). June 14, 5:00 PM - Observation and penetration of a severe thunderstorm near Hunnewell, Missouri in Marion County near Highway 36, and southward along SR V to near Highway 24 and Stoutsville. The storm was an HP supercell storm that evolved to a line segment after being undercut by strong outflow. An RFD clear slot, rotating wall cloud, and funnel was also observed with this storm during its early stages. Heavy rains, 60 MPH winds, and frequent lightning was also encountered. Conditions causing the storm were a stationary front / outflow boundary, a low pressure trough, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills. A severe thunderstorm watch was also in effect for the area until 8 PM CDT.

40). June 15, 5:00 PM - Interception, observation, and direct penetration of a very severe and tornadic thunderstorm near Lacross, Kansas in Rush County to near Great Bend in Barton County, and along highways 28 / 281 to near Highway 56. The storm was a supercell storm that initiated earlier west of Russell, Kansas. A rotating wall cloud, or even a brief tornado was observed when this storm was first encountered during its early stages and before it split. Later the main southern split was directly penetrated while caravanning with other chaser Dan Shaw and Don Sanderson to report hail sizes. During the core penetrations of the supercell, large amounts of golfball sized hail, with larger 2" (and even one stone to 2.5" baseball sized) also observed. Winds up to 45 MPH, frequent lightning, and heavy rains were also encountered. A wall cloud and RFD was also noted with this storm. Conditions causing the storm were a stationary front and dryline "triple point", a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills, audio, and HD video. A severe thunderstorm watch was also in effect for the area until 7 PM CDT.

41). June 15, 7:00 PM - Observation and penetration of a severe thunderstorm near Saint John, Kansas in Stafford County along highways 50 and 281. The storm was a supercell storm that started as a classic / HP storm, then evolved to a multicell cluster of strong and severe storms near Pratt, Kansas. I was caravanning with chaser Dan Shaw and Don Sanderson on this storm. Hail up to 2", 65 MPH winds, heavy rains, and frequent lightning were all encountered in this storm. At dusk, north of Pratt, and incredible display of mammatus was also observed from SR 61 while Dan gave me a spare antenna to replace the broken one I had. Conditions causing the storm were a stationary front and dryline "triple point", a low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 2 AM CDT the following day.

42). June 16, 5:00 PM - Interception, observation, and penetration of a very severe and tornadic thunderstorm near Madison, Nebraska in Madison County near Highway 81 and SR 91, and southeastward to near Schuyler in Colfax County and Highway 30 off SR 15. The storm was an HP supercell storm. A possible brief tornado was barely visible early in the storms life cycle near Madison, before intense rain wrap ensued. Winds gusting near 70 MPH, frequent lightning, torrential rains, and small hail was encountered. The storm became outflow dominant near Schuyler. Conditions causing the storm were a dryline, low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 10 PM CDT.

43). June 16, 7:30 PM - Observation and penetration of extremely severe thunderstorms from near Columbus, Nebraska in Platte County, and southeastward past Saline County to the SW of Lincoln, and through the Beatrice area in Gage County. The storm was followed via SR 15 out of Columbus to SR 33 / 103 to near Beatrice, and Highway 77 back into Kansas to north of Manhattan in Riley County! The initial stage of this storm complex was an HP supercell near Columbus that became outflow dominant and pushed rapidly southeastward thereafter. The storm merged with an LP supercell storm west of Lincoln, briefly producing funnel clouds. The storm complex, now with an embedded mesocyclone, continued southeastward towards Gage County after dusk, with extreme-damaging (derecho / XDW) winds exceeding 100 MPH. The strongest winds encountered with this system were about 70 MPH. Numerous trees down, wind damage, and power poles snapped were observed near Beatrice, making getting through there nearly impossible. Hail to quarter sized, torrential rains, and CONTINUOUS lightning (many close hits as well) were also encountered. At times the lightning was so frequent (more than 10 flashes per second), that if you turned off your headlights you could still see clearly, as if you were in a nightclub. Flash flooding and wind damage was observed in Beatrice, with power out in most areas. Conditions causing the storm were a dryline / outflow boundary interactions, low pressure area, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 10 PM CDT.

44). June 17, 7:00 PM - Interception and observation of a severe thunderstorm near Memphis, Missouri in Scotland County, along and near SR 15 and Highway 136. The storm was initially an HP supercell storm, but became outflow dominant and evolved to a cluster of storms as it spread southeastward to near Williamstown. The core of the storm was not penetrated, but contained hail up to baseball sized. Conditions encountered were 60 MPH wind gusts, heavy rain, small hail, and frequent lightning. Downed trees blocked some roads, and I used the vehicle mounted winch to clear a tree off SR A to allow passage. Power was also out in some areas. Conditions causing the storm were a stationary front / outflow boundary, a low pressure trough, surface heating, and an upper trough. A 2016 Jeep Wrangler was used to chase the storms. Documentation was digital stills and HD video. A severe thunderstorm watch was also in effect for the area until 1 AM CDT the following day.

This concludes the chase log for the central US Plains for the main chase "expedition" of 2017 starting April 17 and ending on June 26. The summary includes a total of 44 observations, out of which there were 42 severe thunderstorms and 2 strong thunderstorms. Out of these thunderstorms, as many as 21 tornadoes were observed, with at least 6 of them being significant and / or destructive. The main chase vehicle conducting this chase was a 2016 Jeep Wrangler. All entries for the logs above are for the local time zone unless otherwise noted. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.


GALLERY FOR APRIL 17-18, 2017

Packed up and leaving south Florida on April 17, passing through Orlando, Florida and planning to spend the night in Gainesville, Florida.
View of non severe storms in the distance from along I-24 passing through Tennessee en-route to Saint Louis during the afternoon of April 18.


GALLERY FOR APRIL 19, 2017

Today was a chase day, the first of this trip. The target area was anywhere from NE Kansas, SE Nebraska, and into NW Missouri / SW Iowa. In the images above, to the left is MCD 519 issued for the target area by the SPC (prior to tornado watch 148). In the middle image, the 2245z visible satellite shows storms are firing along the Pacific cold front and dryline intersection in SE Nebraska (circled). To the right, is a radar image (reflectivity) showing one supercell storm near Lincoln, Nebraska producing a possible tornado.

My chase vehicle prepared for hail (grills installed) late in the day on April 19, 2017 near Eagle, Nebraska.
View looking west towards a developing supercell storm near Lincoln, Nebraska from near Eagle. Note the wall cloud and scud tags.
Possible tornado or rotating wall cloud near Lincoln, Nebraska looking west from near Eagle. This was the only storm in that area along the line segments with such rotation.
Rotating wall cloud northeast of Eagle, Nebraska as the storm weakens.
Wall cloud and occlusion of HP supercell storm just east of the Iowa / Nebraska border before the storm weakened.


GALLERY FOR APRIL 20, 2017

Today was a marginal chase day with low expectations that were realized south of a warm / stationary front over northwestern Texas late in the day. However, a strengthening low-level jet and arrival of upper air support after dark fostered supercells capable of very large hail after dark. In the graphic above, severe thunderstorm watch 152 is shown to the left, issued for the area after dark by the SPC. The middle image is the IR satellite image, showing supercell storms developing north of the warm front well after dark (445z the next day, or after 10:45 PM CDT on April 20). The annotation shows where the warm front was located, and how the low level jet was crossing it, providing isentropic lift and elevated convection is the EML environment after dark. To the right, we see two powerful elevated supercells near the Red River between Altus, Oklahoma and Vernon, Texas on the radar base reflectivity out of Fredericks, Oklahoma after 10 PM CDT. These storms produced hail to at least tennis ball sized.

Looking aouth of a brief LP storm that failed to sustain itself over Haskell County, Texas late in the day on April 20.
The low level jet (LLJ) intensifies and produces these laminar cloud formations as air above it is lifted isentropically. The highly sheared cloud "tower" in the background will eventually develop into an elevated supercell north of the stationary front and produce tennis ball sized hail.
Intense elevated supercell storm and inflow into it as a lightning bolt strikes in the foreground. This was at about 10:30 PM CDT and north of Vernon, Texas on April 20. The view is west from Highway 283 as the storm is producing hail to tennis ball sized.
VIL (Vertically Integrated Liquid) image of these two elevated supercells after dark showing values at the top of the VIL scale (80 VIL)! This means these storms are producing extremely large hail (most likely approaching baseball sized, especially on the cell to the lower left).


GALLERY FOR APRIL 21, 2017

Today was a chase day from north-central Texas and south-central Oklahoma and points eastward. Basically a Pacific cold front was to overtake a dryline, and a diffuse stationary front extended to the east across SE Oklahoma. In the left image above, tornado watch 155 was issued for the target area, valid until 1 AM CDT the following day. In the middle, the visible satellite at 2245z shows the storms firing and becoming supercells from south-central Oklahoma and eastward to near Hugo. The annotations also depict the Pacific cold front and dryline positions at the time. To the right is the base reflectivity image of the main supercell storm west of Hugo and east of Durant, Oklahoma at approximately 6:49 CDT.

Australian chaser Daniel Shaw joins me on the April 21 chase in Texas / Oklahoma during the afternoon.
Convective initiation while meeting with as local farmer on his ranch outside of Gainesville, Texas.
Developing supercell storm (50 miles away) viewed from a farmers ranch north of Gainseville, Texas - Looking northeast.
View of supercell storm from past Durant, Oklahoma.
Suspicious large funnel (or wall cloud) behind the RFD clear slot (center of photo) viewed from a distance past Durant, Oklahoma.
The supercell near Bennington, Oklahoma begins to weaken, but not before displaying this "stacked plates" structure on it's southern side.
The sky takes on an eerie green color at dusk while passing between two severe hail storms.


GALLERY FOR APRIL 22-23, 2017

While stopping at Home Depot in Paris, Texas, I came across these tornado shelters for sale. And, you get a free cruise (in the Central USA?) if you purchase one!
April 23 was another off day, so I decide to do some skydiving at Skydive Spaceland Dallas northeast of McKinney, Texas.


GALLERY FOR APRIL 24, 2017

April 24 was an off day and was spent re-positioning north to Oklahoma City.


GALLERY FOR APRIL 25, 2017

Today was a marginal chase day, with the potential of supercells and an isolated tornado late in the day in north-central to northeastern Oklahoma late in the period. In the left image, a 5% tornado probability in a small area is depicted on the SPC 1630z convective outlook. The middle image is the visible satellite at around 2245z, showing storm initiation east of I-35 in north-central Oklahoma. This was ahead of a slow moving Pacific cold front and in an area of pre-frontal convergence. The right image is much later after dark, and shows a supercell storm southwest of Tulsa, Oklahoma on the base-reflectivity product.

Convective initiation underway to my west, looking westward towards a small supercell developing near Stillwater, Oklahoma on April 25.
Eerie green color of a developing hail core (to the right in this picture) while heading south on SR 18 towards Pawnee, Oklahoma.
Wall cloud associated with an HP supercell storm near Pawnee, Oklahoma. The view is WNW.
Wall cloud before occlusion of and HP supercell near Pawnee, Oklahoma and transition to a line segment of severe thunderstorms.
Small hail blows into my hotel room southwest of Tulsa, Oklahoma during late evening passage of an MCS on April 25.


GALLERY FOR APRIL 26, 2017

Today was a chase day that should have had high hopes and a high return on an outbreak of tornadoes. Instead, the result was a squall line and outflow dominated storms, and not a single tornado report in the expected target area, as well as within the 15% hatched moderate risk outlook for tornadoes progged by the SPC. The 15% hatched graphic is shown to the left. In the middle image is tornado watch box 162 valid until 5 PM CDT, and just east of former severe thunderstorm watch 161. To the right is the base reflectivity image just prior to 5 PM CDT showing a messy and weak squall line as the result of the surging Pacific cold front and outflow essentially averting a tornado disaster.

This was to be the most "spectacular" shot of the day, despite a high-end moderate risk issued by the SPC. Here a shelf cloud / gust front approaches a cemetery near Magnolia, Arkansas on April 26.
View of "whales mouth" (backside of shelf cloud) near Magnolia, Arkansas.
This is the view most storm chasers will have chasing in many parts in Arkansas. Even if there was a large tornado, it would be difficult - and dangerous - trying to see it through these trees!


GALLERY FOR APRIL 27, 2017

April 27 was a down day / reposition to Oklahoma from Texas. Looking overhead during the afternoon, the strong jet streak (125+ knots at the jet stream level) causes streaking / "herring bone" waves in the fast moving high clouds.


GALLERY FOR APRIL 28, 2017

Today was another chase day that looked rather promising, up until the early morning data analysis, with some chasers grudgingly leaving the Oklahoma target (one chaser spending less than an hour in his hotel in Gainesville, Texas and checking out without a refund to go east) to the higher tornado probabilities hundreds of miles farther east over the Midwest / Dixie area. An extremely large, "hot dog" shaped area of enhanced risk was issued by the SPC, stretching from just east of the Texas Panhandle to nearly as far east as southwestern Ohio! A 10% tornado outlook was issued for western Kentucky, with a 5% tornado probability (later upgraded from 2% extending westward). This is shown in the far right image. Not shown is a 30% hatched hail probability and 15% wind for the enhanced risk zone. The two images to the left are the soundings from DFW and OKC, respectively. The "nose" shaped temperature plots on each clearly denote a capping inversion that ensures no storms will develop without any upper air forcing. Note the middle image showing a "double" temperature inversion.

Waiting for storms under a strong cap (temperature inversion aloft that suppresses storm development) in Pauls Valley, Oklahoma with Jerry Prsha and his chase partner late in the day on April 28.
By looking at the tops of the cumulus clouds struggling to develop vertically near the warm front over south-central Oklahoma, it becomes apparent the capping inversion is holding. The flat tops of the clouds denote the inversion is present by early evening on April 28.


GALLERY FOR APRIL 29, 2017

Today was a chase day with low expectations and ended up being one of my top tornado intercepts! Basically the target area was to be anywhere from near Paris, Texas and southward to the north of Waco near the I-20 area and Mineola, which lies to the east of the Dallas area by about 100 miles or so. In the left image above, we see the SPC issued MCD 594 (prior to issuance of tornado watch 175) for the same area. The MCD highlighted the risk of damaging winds and hail, but not much emphasis on tornadoes, owing to a surging Pacific front to the west, and expected storms to be linear in nature. In the middle annotated visible satellite (around 2015 CDT), we do not see any significant storms yet. However, there are some extremely important features to be noted. One is the developing convection (circled), with an area of agitated cumulus coinciding with CAPE values in excess of 5000 J/KG. Another is an outflow boundary pushing westward from a decaying complex of storms that formed during the morning over western Louisiana. This outflow became highly modified, and provided an environment characterized by SE to ESE (backed) winds, temperatures in the upper 70's to low 80's, and dewpoints in the mid 70's feeding into the target area later in the day. Without this feature, south to SW winds would prevail with temperatures near 90 and a dewpoint in the upper 60's, and the Pacific front would have quickly overspread the area. Finally, to the right, is the visible satellite at 2345z (6:45 PM CDT) showing the tornado producing supercells still ahead of the more benign squall line pushing in from the west. A large tornado was on going at the time of the right image near Fruitvale, Texas.

Shelf cloud associated with one of many outflow boundaries in south-central Oklahoma early on April 29.
Approaching a soon to be violent cyclic tornadic supercell back-building to the south of Canton, Texas (Highway 19) at around 6 PM CDT on April 29. This storm has a developing tornado that will affect Eustace and Tundra with a weak rain wrapped tornado, then ultimately a strong to violent tornado afterwards. Note the "fog" to the left just above the roadway, caused by the intense pressure drop (ears also popping) under the supercell tornado cyclone!
Possible view of the Eustace to West Canton tornado becoming rain-wrapped. The left edge of the tornado can be seen left of the center of this picture. This tornado was rated EF-4 and was a violent, but less visible tornado. The view here is from west of Highway 19 near Tundra and looking towards the WSW at around 6 PM CDT.
This is what appears to be another tornado (but probably weak and EF-1 or less) also rain-wrapped and passing west of Highway 19 near Tundra, Texas at around 6:05 PM CDT. The view is southwest. I think this may be a satellite vortex going around the main Eustace to W Canton EF-4 tornado that was not visible at the time to my WNW. A loud roar was also audible at this time.
Developing strong tornado crossing road looking southward on Highway 19. This tornado will become a very large tornado causing at least EF-3 damage. This was NOT the same tornado that was rated EF-4 and passed west of Canton and was rain-wrapped - And probably still on going as this one was starting!
Close-up of tornado core flow crossing Highway 19 (from about one mile to the north) looking southward.
Frightening silhouette of the tornado approaching high-voltage transmission lines. The tornado is widening and intensifying rapidly. The view is south and southeast.
Maturing tornado at about 6:15 to 6:20 PM CDT destroying transmission pylons to the southeast of Canton, Texas. Tornado at LEAST EF-3 strength at this point. The view is to the southeast.
Tornado at about 6:20 PM CDT in wide wedge phase, continuing to the NE and just about to hit the eastern side of Canton, Texas. The view is to the east.
Wedge tornado still widening and incredible low level mesocyclone looking eastward out my passenger window from Highway 19 in Canton, Texas. The tornado is about to cross I-20 at this point.
Heading east on I-20 and coming across many people seeking shelter under this highway overpass. This is NOT a place to be in a tornado, and is obviously obstructing traffic.
Massive wall cloud / violently rotating mesocyclone and RFD cascading looking northward from I-20 at 6:30 to 6:35 PM CDT. The car dealership that got destroyed is to the right in this picture. These were extremely fast moving clouds.
View of devastation to the car dealership seconds after the tornado hit on the north side of I-20 at around 6:35 PM CDT.
More damage looking north of I-20 seconds after the tornado passed through on the east side of Canton, Texas. Unfortunately this storm killed at least 5 people from Canton to Fruitvale farther north.
Looking north and northwest from Highway 80 on the eastern side of the damage path in Fruitvale, Texas at roughly 7 PM CDT. Note the home to the right missing a roof. I was unable to get farther into the damage path due to roads blocked. In this picture, the tornado is still visible in the sky moving off and becoming rain wrapped to the right.


GALLERY FOR APRIL 30, 2017

Today was a highly conditional chase / travel day, with a trip up north, eventually to the Chicago area. Tornadic storms were mainly rain-wrapped, if any, and very early in the morning in the deep south. SPC depicted this on the 13z outlook, with a 10% chance of tornadoes. This is shown in the left image above. Later on, limited instability and a surging front / outflow trumped the probabilities substantially. The 20z outlook as per SPC for tornadoes was drastically less as shown in the middle image, with the 5% in my northern target essentially gone. To the right is the visible satellite, at around 1515z, showing extensive morning convection over the deep south, probably containing bows and embedded (rain wrapped) tornadoes. Note the intense low pressure area to the left of that image over western Oklahoma, and even snowfall over those areas!

Major flooding was also a part of this weather system passing over the central USA around April 29-30. This is one of many flooded scenes across Arkansas (Lonoke in this case).
Small and low topped storms struggled to develop near the warm front in Illinois, but couldn't sustain themselves.
Broken power pole and flooding in southern Illinois off I-57. The water to the left is a flooded farm, NOT a lake!


GALLERY FOR MAY 1-9, 2017

Flooded backyard in the suburbs west of Chicago, Illinois while spending off time there starting on May 1. The water levels may remain high for up to a week after this storm system.
May 1-9 was off-time and I took a break from storm chasing, spending the off-time in Chicago and back in south Florida, returning May 8 to the central USA. In this picture, I am enjoying the Fort Lauderdale air show on May 7.
May 9 was a trip back out to the Plains from Chicago (after arriving back there May 8), and meet up with Derek Sibly who drove out from Alabama that same day. In this picture we are visiting the memorial for Tim and Paul Samaras / Carl Young near El Reno, Oklahoma before heading west to Clinton for the night.


GALLERY FOR MAY 10, 2017

May 10 was the first chase day after about a week of off / down time. In the images above, the left image shows MCD 684 issued by the SPC. This pretty much outlines our target area (I was chasing with Derek Sibley May 10 and 11) for the day. In the annotated middle image, the main storms are shown on the visible satellite at roughly 2345z (6:45 PM CDT). To the right is one of the base reflectivity radar images of an intense supercell storm at about the time we were punching through its hail core and a weak tornado was being produced.

Impressive "whales mouth" (turbulent backside of shelf cloud) associated with the passage of a severe thunderstorms gust front during the morning of May 10 in Clinton, Oklahoma.
View penetrating the hail core of a supercell storm between Childress and Matador, Texas along a ranch road near Cee Vee. Most of the hail here is quarter sized, but will approach baseball sized later on!
Intense RFD clear slot and rain free "horseshoe" base north of Quanah, Texas and near the Red River.
Storm chasers observing the gust front and outflow of the former supersell storm approaching Altus, Oklahoma during the afternoon of May 10. Tim Marshall is there with the TWIRL group in the foreground.
Severe street flooding in Altus, Oklahoma after passage of the HP to MCS storm complex!
New LP supercell storm developing on the dryline father southwest towards Odell, Texas and west of Highway 283 late on May 10.
Gustnado dust and RFD winds near Highway 283 and 287 as the LP supercell evolves to classic mode late on May 10.
Possible brief (but weak) tornado north of Davidson, Oklahoma. Note the RFD slot to the left. The possible tornado is in the center (or slightly right of) in this picture.
Lightning illuminated shelf cloud with weak shear funnel / scud tag with my Jeep in the foreground while ending the chase after dark on May 10.


GALLERY FOR MAY 11, 2017

May 11 was another chase day, and storms developed rather early and shortly after the SPC issued MCD 694, as shown to the left in the images above. The middle image is an annotated visible satellite at roughly 2245z (5:45 CDT), and shows the upper low, dryline, and storms developing over NE Oklahoma as well as the cold core near Oklahoma City. To the right is a base reflectivity image, showing a supercell near Kingfisher, and convective initiation over north-central Oklahoma at roughly 2 PM CDT.

Convective initiation looking northward on I-35 and approaching Guthrie early in the afternoon on May 11.
View of hail along the side of the road while approaching the supercell storm that initiated near Kingfisher and is now near Perkins, Oklahoma while catching up to it after a fuel stop.
View looking NW from near Cushing, OK as the HP storm was becoming outflow dominant. The wall cloud (note RFD cut as well) is being undercut, and the storm is evolving into a line segment.
View of gust front and shelf cloud of the MCS as it approaches Pawnee County, OK during the afternoon of May 11. One of the chase tour vans is having problems with blue smoke coming out of its exhaist up the street as well.
View of rain free base on the south side of the line segment pushing through Sapulpa, Oklahoma.
Elevated LP supercell storm looming over I-35 in Oklahoma City, Oklahoma during the late afternoon / early evening of May 11 as the cold core moves overhead.


GALLERY FOR MAY 12-13, 2017

May 12 was an off day and the start of another lull in the activity for a few days. Derek headed home for a while and I am getting routine service done (oil changed) on my vehicle in Oklahoma City due to the high mileage. May 13 was also an off day and was spent near Denton, Texas before heading back west for the next approaching setup.


GALLERY FOR MAY 14, 2017

May 14 was a marginal chase day in and around the Amarillo, Texas area while re-positioning near there from the Denton area early in that day. In the images above, the left image is the SPC outlook, showing a marginal risk for the Texas Panhandle area (plus an additional area near NE Colorado). In the middle image, MCD 714 is shown issued by the SPC for isolated severe thunderstorms. To the right is a visible satellite image from roughly 2345z, annotated showing key features of the storm development.

Convective initiation looking westward from Highway 287 towards Amarillo, Texas early in the afternoon on May 14.
High-based marginal supercell storm developing between Amarillo and Dumas looking west of Highway 87 / 287. The precipitation (containing small hail) mostly is evaporating before reaching the ground. The cloud base appears "glacial" because itís above 10 or 15 thousand feet (MSL).
View looking northeastward from near Dumas, Texas at a distant supercell storm explosively developing 85 miles away north of Guymon, Oklahoma
This small high-based funnel developed on an LP storm as part of a cluster of storms near Claude, Texas.
Spectacular view of hail shaft of a severe thunderstorm over the Palo Duro Canyon in Texas (SE of Amarillo) late in the afternoon of May 14.
View of backside of storm anvil spreading out north of Panhandle, Texas late in the day near sunset on May 14.


GALLERY FOR MAY 15, 2017

May 15 was a marginal (slight risk) chase day with several areas of storm possibilities across the USA as depicted by the SPC graphic in the left image above for 1630z. The area of greatest interest is the slight-risk in the Texas Panhandle. The middle image is a visible satellite image, showing the storms that did develop along the dryline in the central TX Panhandle by about 2345z. To the right is a radar reflectivity image of the supercell storm near Stinett, Texas at about that same time.

Convective initiation to the north of Amarillo, Texas late in the day on May 15.
Mature supercell storm near Stinett, Texas. The storm had a classic supercell structure, with "stacked plates" appearance.
Strange mid-level funnel near a mid-level inflow band to the northeast of the Stinett, Texas supercell.
Copious amounts of hail at least golfball sized covering the landscape to the north and east of Stinett, Texas.
One of the larger pieces of hail picked up off the side of the roadway northeast of Stinett.
Large wall cloud forming as the supercell back-builds and moves near Waka, Texas at about 9 PM CDT in twilight. The view is towards the northwest from Highway 84 near Canadian, Texas on May 15.
Possible brief tornado forms off the rotating wall cloud near Waka, Texas at about 9:15 PN CDT. The remaining twilight provides good contrast.
Intense CG lightning bolt and wall cloud near Waka, Texas during the evening of May 15.


GALLERY FOR MAY 16, 2017

May 16 was a pretty busy chase day with destructive tornadoes developing near the eastern Texas Panhandle areas and into SW Oklahoma. The left image is the 1630z SPC tornado probabilities, showing a 15% hatched area. The area was under a moderate risk as well. The middle image is an annotated visible satellite showing the tornadic supercells developing ahead of an active dryline after 2245z. To the right, most impressively, is the close-range DOW (mobile Doppler) image from the TWIRL research group, of the Elk City, OK tornado nearing peak intensity. The reflectivity shows a spiraling presentation, and the tornado core itself has a clear and distinct "eye"! The inset of the right image is the Doppler velocity of the tornado, with 195 MPH winds measured a few hundred feet above the ground. Also, in the right image, our position would be just left of the "eyewall" surrounding the "eye" in the black / blue inflow "slot" to the lower left. That's about the same time one of the pictures below was taken (with the roof airborne)!

One of the first supercells of the day develops near the intersection of a surface boundary and dryline at roughly 3:30 PM CDT to the west and northwest of Perryton, Texas on May 16. The view is to the west, looking at the classic supercell storm updraft and anvil blowoff overhead.
The storm produces a small cone tornado (ground circulation confirmed by another observer closer in) to the northwest of Perryton, Texas. The image is from a highly zoomed video frame grab.
Here is a picture of a persistant funnel on the classic supercell storm as it moves northeastward towards the OK / TX border into Beaver County, Oklahoma.
After abandoning the storms to the north, we headed south and penetrated the Wheeler, Texas supercell. This view, looking east from just south of town, shows the wet RFD. A large rain-wrapped tornado is in there, not visible, but probably to the left in this picture.
Downed powere poles and debris along Highway 83 south of Wheeler, Texas after the passage of a rain-wrapped tornado. One person was killed from this tornado.
Yet another supercell storm develops on the southern portion of the complex of supercell storms. This is looking ESE towards Erick, Oklahoma from near I-40 and Highway 83. This will produce the tornado that hit Elk City, killing one person and causing damage on the south side of that town.
This is the Elk City tornado in its development stages (multi-vortex / wedge) southeast of Erick and southwest of Elk City, Oklahoma late in the afternoon, early evening on May 16. The view is north and northeast.
Heading east on SR 152, extremely large hail smashes into the roadway in front of us. This is a stone about 4" (between baseball and grapefruit sized) smashing into the road and shattering.
Approaching the developing (and rain wrapped) wedge tornado from the west on 152 and southwest of Elk City. The view is to the east, with the northern edge of the tornado visible.
Southern edge of the wedge tornado intensifying and taking aim on Elk City while stopped in powerful rear inflow jets and looking east on SR 152.
Debris blowing around and on the side of SR 152, to the right, a building is being destroyed and the metal roof is airborne with white spray or material streaming out (grain / flour?).
This is the view looking northward towards Elk City (which would be far left in this picture). The tornado is rain wrapped and not visible. Note the tremendous inflow features going from right to left behind the wet RFD surge in the foreground and to the left.


GALLERY FOR MAY 17, 2017

May 17 was an off day despite distant chase prospects in Iowa, we decided to stay in the Oklahoma City area to catch up as May 18 was to be another busy chase day. In this picture, we are doing a damage survey in Elk City, Oklahoma after the tornado there a day prior, which caused extensive damage to the south side of the city.


GALLERY FOR MAY 18, 2017

May 18 was a very high stress (and high risk) chase day in Oklahoma. The SPC had a high risk issued for the area in their 13z and 1630z outlooks, and a hatched area of 30% tornado probabilities. Despite this high octane setup, weak capping caused storms to develop everywhere, yielding a large messy area of storms with embedded tornadic supercells - Not the highly feared, discrete long track violent supercells expected. The left and middle image shows the SPC high risk and tornado probabilities, respectively. The annotated visible satellite image to the right, at roughly 2245z, shows the large area of thunderstorms developing ahead of the dryline and south of a stationary front as upper air support moves in from the NW. One tornadic supercell, shown in some of the pictures below (near Waynoka and Avard) is circled in the right image at about the same time it was producing tornadoes.

Ominous view near Fort Supply, Oklahoma looking NW at a developing supercells core on the high-risk chase day of May 18 during the early afternoon. This is NOT a tornado, but a descending wet microburst loaded with rain and hail.
View slicing through the hook of an HP supercell west of Alva, Oklahoma with the radar image of the storm in the foreground on the Smartphone.
Possible rain-wrapped tornado to the west and northwest of Alva, Oklahoma on May 18. The tornado would be to the left in this picture. The view is to the east.
First view of the Waynoka tornado from near Avard, Oklahoma looking to the west and southwest during the afternoon of May 18. The tornado, although weakening, is in the center of this picture. The next storm "cycle" is to the left of that (funnel / rotating wall cloud).
New rotating wall cloud / funnel near Avard on the Waynoka cyclic supercell. The storm was classic structure, with a striking visual appearance.
Funnel and supercell structure with a teenager (from a local farmstead riding his dirtbike) watching it. The view is to the west near Avard, Oklahoma.
Rotating wall cloud / funnel on the weakening supercell as it moves west of Alva, Oklahoma from near Avard.
Former supercell storm near Custer City, Oklahoma becoming outflow dominant ahead of the dryline and evolving into a bow segment late in the day on May 18.
Mammatus and interesting gravity waves over Clinton, Oklahoma during the evening of May 18.


GALLERY FOR MAY 19, 2017

May 19 was a chase day that originally was to be in SW Oklahoma, but a pesky MCS overnight from May 18 pretty much ruined that forecast by the morning. The day was presented with a very difficult forecast and basically there were two areas to target: One in south-central Kansas with high shear and weak instability, and the other with moderate shear and high instability in central Texas. Being in SW Oklahoma, we decided to head south. At the end of the day, the tornadoes would form, in - you guessed it - the Kansas target. The left image shows a large 5% tornado area depicted by the 1630z convective outlook by the SPC. In the middle, the annotated satellite image at 2245z shows the complicated evolution of convection along the target area(s), influenced by outflow boundary undercutting and frontal interactions. To the right image, is a base reflectivity of a supercell storm south of Abilene, Texas that briefly became tornado warned.

Shelf cloud north of Archer City, Texas during the early afternoon of May 19.
Gust front and shelf cloud associated with elevated severe storms passing over Graham, Texas during the early afternoon of May 19.
Wall cloud on supercell storm before being undercut by outflow near Archer City / Graham, Texas during the early afternoon of May 19.
Weakly rotating wall cloud to the west and southwest of Coleman, Texas on an outflow dominant supercell storm during the afternoon of May 19.
View of developing LP supercell storm to the northwest of Acampo, Texas on May 19. Note the beautiful pileus cloud cap, and jet airliner passing the storm tower to the left.
Supercell storm and roll cloud looking northwest from near Acampo, Texas.
Interesting roll cloud moving across the Texas plains late in the day on May 19 near Acampo, Texas.


GALLERY FOR MAY 20, 2017

View of sky with ACCAS (altocumulus castellanous) clouds over I-35 while heading northward to Oklahoma City out of Texas.


GALLERY FOR MAY 21, 2017

May 21 was a highly marginal and conditional chase day. The only area that struck any interest (and possibilities) for supercells would be from the western Texas Panhandle and westward into the higher terrain of eastern New Mexico. This area was on the edge of a marginal risk as per SPC, and southwest of a boundary many other chasers targeted (that area only yielding linear storms). No watches were issued, and the MCD for my target area is shown to the far left. The middle image, a visible satellite at roughly 2345z, supercell storms can be seen in eastern New Mexico, and linear storms farther north near the OK Panhandle and far SW Kansas. In SE Texas, a large storm cluster stabilized the atmosphere. In the far right image (radar reflectivity), a classic to HP supercell image can be seen over eastern New Mexico south of Tucumcari that I was chasing at the time.

View of sky in western Texas just east of the New Mexico border near Vega late in the day on May 20. The weak convective showers have hail and snow aloft due to the colder environment just above the surface in the high plains.
Approaching two supercell storms near Tucumcari, New Mexico late in the day on May 20. The view is west on I-40 at the northern storm, which is weaker and high based. Note the inflow bands to the left.
Large rotating wall cloud / funnel, and possibly a developing tornado looking to the southwest off I-40 towards Quay County, New Mexico.
Closer view of this funnel / tornado over Quay County, New Mexico. The view is to the southwest from I-40 at about 7:15 PM CDT (6:15 mountain).
Rotating wall cloud / or even a dusty tornado on the persistent storm in Quay County, New Mexico looking west from SR 206. This was roughly 6:30 MDT (7:30 central). The storm had a well-defined couplet and hook at the time, but began weakening after that.
View of laptop with radar image (base reflectivity) of the supercell storm in the foreground, and the storm itself out the passenger side window to the west.
Full wide angle view of an impressive rainbow at sunset in Quay County, New Mexico.
Myself fueling up the vehicle with the rainbow behind me in open country in New Mexico. There is no place to get gas in these areas, so carrying spare fuel is a MUST.


GALLERY FOR MAY 22, 2017

May 22 was another chase day in eastern New Mexico, not far from the previous day's setup, but a tad farther south. In the left image, a large slight risk area issued by the SPC at 1630z extends from eastern New Mexico and southeastward into central and western Texas. Due to upslope wind flow, the far NW edge of the slight risk was where my target area was. The middle image is a visible satellite (after 2345z) showing the main supercell pushing southeastward across eastern New Mexico and east of Roswell. To the right is a base reflectivity radar image of the same storm at the time it was intensifying. Note the prominent hail spike extending southwestward out of the storm core (radar site was Canon AFB northeast of the storm).

View of first small supercell of the day encountered west of Portales and Floyd in eastern New Mexico during the afternoon of May 22. The view here shows the RFD clear slot, looking towards the southwest. Small hail was falling at the time.
Grass fire started by a "dry" lightning strike over rural areas west of Portales, New Mexico.
Intensifying LP supercell storm to the northwest of Highway 70 near Kenna, New Mexico. The storm is producing large hail at this time. The view is to the west.
High based wall cloud over Highway 70 near Elkins, New Mexico late in the afternoon of May 22. Large hail is to the right. The view is to the west and southwest.
Incredible updraft of the supercell storm moving southeast over Chaves County, New Mexico east of Roswell. The storm was tornado warned at this time. The view is to the east on Highway 380.
View of weakening LP supercell storm south of Highway 380 and mammatus / anvil blowing off to the left. The view is to the south.
Dan Shaw on Highway 380 east of Roswell, New Mexico in his chase vehicle, as the supercell storm weakens in the background over Chaves County.
The weakening supercell storm produced a large canopy of mammatus clouds, under-lit by the setting sun late in the afternoon / evening of May 22.
This is what was left of the "raging" supercell over Chaves County, New Mexico. In a process called down-scaling, the storm basically shrinks until its no more. This rotating cumulus is what is left just prior to the storm evaporating to nothing.


GALLERY FOR MAY 23-24, 2017

These days were off days / travel days without much in the way of storms. This is a picture of the main street in the small town of Weatherford, Oklahoma.


GALLERY FOR MAY 25, 2017

May 25 was a marginal chase day in the upslope flow of eastern Colorado and into far western Kansas. The same area of concern is outlined by an MCD issued by the SPC later in the day, and is shown in the left image. The middle is a visible satellite at about 2245z showing the supercell storms moving out of eastern Colorado and western Kansas. The right image is a base reflectivity image of the supercell storm near Idalia, Colorado with a "swirl" near the center of the image denoting strong rotation.

Developing supercell storm over Yuma County, Colorado during the afternoon of May 25. The RFD slot can clearly be seen just below the center of the picture, although the base of the storm is still high. A lower cloud base is barely visible to the right of that. The view is northwest.
Hail fog and some dust blowing from north to south across highway 36 looking east. This was to the south of a rapidly intensifying supercell storm.
Weak tornado viewed from inside the hail core looking east north of the Bonny Reservoir and east of Idalia, Colorado. Time is roughly 3:30 PM MDT on May 25.
Hail covering Highway 385 just behind the Idalia storm.
Weakening storm to the west of Wheeler, Kansas. The view is to the west, and the storm base is again higher after the wet RFD has occluded.
Large wall cloud (before getting undercut by outflow) to the southwest of Wakeeney, Kansas later on as the southern supercell begins to wind down late on May 25.


GALLERY FOR MAY 26, 2017

May 26 was another chase day, in similar areas in eastern Colorado as the day before. This area was under an SPC slight risk, and the left image shows the MCD issued for the target area as well. Storms were to develop by mid afternoon in the upslope flow near and east of the Palmer Divide, and track eastward from near Byers along Highway 36 and into Kansas. The middle image is an annotated visible satellite image at about 2345z, showing the supercell storms pushing out of eastern Colorado and into western Kansas. To the right, is a base reflectivity image, showing the hook of the supercell - The white circle is my location (inside the "Bear's cage")!

Upslope convection (convective initiation) west of Byers, Colorado during the afternoon of May 26. This "innocent" looking cloud will become a long-track supercell that will last nearly 8 hours!
Funnel on intensifying supercell storm off Highway 36 east of Byers, Colorado.
Supercell storm intensifying north of Highway 36 and entering Yuma County in Colorado.
Area of intense rotation deep inside the "bear's cage" of the storm north of Anton, Colorado. Isolated baseball sized hail was falling at the time. The rain / hail "core" just left of the center of the photo is rotating hard and can possibly be a weak tornado.
Impressive view of the storm near Goodland, Kansas off I-70.
Lightning illuminated HP storm evolving to bow segment near Goodland, Kansas late on May 26. There are a few funnels on the forward flank of the storm.


GALLERY FOR MAY 27, 2017

May 27 was another chase day with great expectations and a windfall at the end. A moderate risk was issued by the SPC at 13z and 1630z, and the main threats were wind and hail. A hatched 10% area was on the western side of the moderate risk, and my target area was in NE Oklahoma for starts. The middle image shows the MCD issued for the area by the SPC, prior to issuance of a tornado watch box. To the right, is an annotated satellite image of the area at about 45z the following day (UTC), showing a complicated setup with a dryline, stationary / cold front, and a few supercells firing. This day did not pan out as expected, and any supercells that did develop quickly became undercut or weakened / became linear.

Convective initiation looking eastward from near Pawhuska, Oklahoma. This was a linear storm complex along an outflow boundary late in the day on May 27. Another isolated supercell will soon develop west of this area and produce large hail.
Supercell storm developing near Pawhuska, Oklahoma looking westward. The storm was a classic supercell storm during its early phases. Note the anvil blowoff and sharp anvil edge.
Hail up to golfball sized in the roadway near Nowata, Oklahoma as the supercell passes overhead.
The short-lived supercell storm becomes outflow dominated and evolves to a bow segment. In this view, we see the outflow and "green colored" hail core to the left. The view is to the northeast near Adair, Oklahoma.


GALLERY FOR MAY 28 - JUNE 11, 2017

May 28 through June 11 was an extended period of "down time" with minor chase prospects and a lengthy period of quiet weather in the central USA. I travelled back to Chicago on May 28 to spend a few days there, and then back to Florida for a few days to take care of some dental and doctor appointments. I returned to Chicago after that, and waited there until a more active pattern resumed across the central USA after June 10.

Small distant cumulonimbus while driving along I-55 near Normal, Illinois en-route to Chicago on May 28.
This is a picture of the southern edge of a severe storm over western Wisconsin is being passed while en-route to South Dakota from Chicago and crossing the upper Mississippi River.


GALLERY FOR JUNE 12, 2017

June 12 was a high-end chase day after a period of quiet weather across the central USA. The SPC had a moderate risk at 1630z over the tri-state area of Wyoming, Nebraska, and South Dakota, with a 15% hatched (for significant) tornado probability over the area, and is shown in the left image. The middle image is the mesoscale discussion 995 issued by the SPC prior to PDS tornado watch box. To the right is the visible satellite image, with annotations, showing the setup as storms were on-going and producing tornadoes. Two major areas are depicted, one along a boundary to the north, and another southward out of NE Colorado, most likely influenced by the Denver Cyclone Vorticity Zone (DCVZ) in upslope regime. This upslope area is actually BEHIND a cold front that passed through this area a couple days prior.

A sign of things to come ... Interesting cloud formations streaming over southwestern South Dakota on June 12, 2017. This is elevated / altocumulus type convection from the lead impulse ahead of a short-wave trough, signaling the arrival of upper level support for severe weather later that day.
Horizontal convective rolls over eastern Wyoming during upslope wind flow and cumulus formation on June 12. The cap is still holding in place, and storms have not formed yet.
Rotating wall cloud on northern tornadic supercell coming into view near Fort Laramie, Wyoming. The view is to the southwest.
My vehicle and approaching supercell storm southwest of Fort Laramie, Wyoming.
Supercell storm and hail shaft looking southwest of Fort Laramie, Wyoming. Softball sized hail was falling from this storm at the time. Note the developing tornadic circulation just below the center of the picture.
Stovepipe tornado barely visible through the rain west of Highway 85 and 26 near Lingle, Wyoming. The view is to the northwest.
Former tornado occludes with impressive RFD, looking west of Highway 85, and new mesocyclone is developing to the right.
New tornado develops north of Lingle and west of Highway 85.
Tornado lifting west of Highway 85 and north of Lingle as the storm becomes HP and occludes again.
This is a view looking south towards Harrisburg, Nebraska on Highway 71. The last tornado of the southern supercell (with a long history of producing tornadoes from NE Colorado to Nebraska) can be seen to the lower right just above the road.
Cyclic supercell moving northwest of Bridgeport, Nebraska late on June 12 and crossing Highway 385. The storm is HP and becoming outflow dominant at this point.
Distant view of the storm northeast of Bridgeport, Nebraska looking northward from Highway 26 at dusk. The supercell has a stacked plates presentation with frequent lightning and mammatus.


GALLERY FOR JUNE 13, 2017

June 13 was another chase day, and a very complicated setup for severe weather and forecasting it. In the images above, a 10% tornado probability is depicted on the SPC 1630z enhanced outlook, centered over the tri-state area of SE North Dakota, NE South Dakota, and western Minnesota, which was near the intersection of a warm front and Pacific Cold front. A 5% tornado probability extends southwestward and another area where the Pacific cold front intersects the dryline near the SD / NE border. The middle image is MCD 1013 issued for the area by the SPC. To the right is an annotated image showing the important features and the visible satellite image as storms were on-going at about 2245z. A tornado also formed in Minnesota due to a confluence axis intersecting the warm front, with other tornadic storms developing along the Pacific front, mainly where it intersected the dryline or warm front.

Approaching a supercell storm southwest of Plankington, South Dakota on June 13, 2017. The view is to the south off I-90 with the anvil blowoff overhead.
View of the HP supercell storm southwest of Plankington as it was intensifying.
Storm produces and area of rotation with small funnels as it moves northeast and crosses I-90.
Gustnado near I-90 west of Mitchell, South Dakota as the HP storm becomes outflow dominant.
View into HP supercell storm with large rotating wall cloud / possible tornado just prior to rain wrapping near Stickney, South Dakota. The view is to the southwest. A major couplet was present on Doppler radar at the time (shown below).
Impressive couplet on Doppler radar showing the area of rotation at the time the picture above was taken.
Outflow and blowing dust affecting Mitchell, South Dakota looking north on Highway 81 as the HP storm gusts out and evolves to a line segment with damaging winds along its gust front.
Hail shaft associated with a line segment of severe storms near Hutchinson County, South Dakota. The view is to the south.
Anvil and view of the southern "tip" of the severe storm line segment west of Yankton, South Dakota late in the day on June 13.
Intense portion of the line segment pushing through Cedar County, Nebraska near Bow Valley. The view is to the south and southeast, showing a prominent green-tinted hail shaft moving from right to left.
Severe conditions (winds over 60 MPH and large hail falling) near Bow Valley in Cedar County, Nebraska as the line segment intensifies after dark. This storm complex would make it to near Sioux City, Iowa leaving a swath of power outages and wind damage in its path.


GALLERY FOR JUNE 14, 2017

June 14 was a chase day with a target area in north-central Missouri and points eastward. This was on the SW side of a slight risk area, and included a 2% tornado probability, as shown in the left image as of 1630z. The middle image is MCD (mesoscale discussion) 1026, and clearly shows two areas of instability, one in Kansas near Wichita, and another in my target area in east-central and northern Missouri. To the right is the visible satellite as of 2345z, and is annotated to show important features, such as a stationary outflow boundary and frontal zone, with storms maturing in north-central to NE Missouri. Also, with much of the area capped in between, a small LP supercell is forming on the dryline near Wichita in south-central Kansas.

Convective initiation over north-central to northeastern Missouri during the afternoon of June 14, 2017. Note the tilting of the updraft tower due to the 40 knots of bulk shear in the 6km layer.
View of developing supercell storm near Marion County in Missouri from eastbound on Highway 36. Note the wall cloud in the lower portion of the picture.
View of first of two small funnels developing on the developing supercell storm south of Hunnewell, Missouri over Marion County.
View of classic to HP supercell near Hunnewell, Missouri and Highway 36. Note the prominent RFD clear slot and funnel (second one produced by this storm) in the center of the photo.
View of the small second funnel developing on the north side of a supercell storm's RFD slot north of Hunnewell, Missouri.
View of the storm evolving to HP mode as moisture increases with arrival of the low level jet. The view is to the north and northeast.
Severe winds and torrential rains looking south from behind the gust front north of Highway 36.
The storm produces and area of rotation again near Stoutsville, Missouri. The view is northward from Highway 24 with a brief funnel and rotating scud over a farmstead. The storm became outflow dominated after this and weakened.


GALLERY FOR JUNE 15, 2017

June 15 was a chase day in central Kansas, with a drive out from east of Kansas City, Missouri. As of 1630z, a moderate risk was in place in a small area in central Kansas as per the SPC, and is shown in the left picture. Unlike many moderate risks, the inset shows only a 2% tornado probability, as the threats on this setup would mainly be strong winds and large hail, due to weak low level shear. In the middle, MCD 1043 outlines the instability area and status on the severe thunderstorm watch area (watch 332). To the right is the annotated visible satellite, rather early, at 1845z. A solitary supercell storm has developed on the triple point of a boundary and dryline intersection owing to extreme instability there (CAPE 5,000 J/Kg or higher)!

Racing westward on Interstate 70 to meet an early initiating supercell developing west of Russell, Kansas on June 15, 2017. The view is looking westward from west of Salina, Kansas. Note the ACCAS clouds overhead as well.
While approaching the storm from the east, and nearing Russell, Kansas, the view to the south reveals the anvil spreading overhead in the NW flow aloft, and lower clouds streaming into the intensifying supercell storm out of frame to the far right.
This was a brief tornado (lower right in this picture) that developed on the south side of the supercell storm. The tornado was confirmed by chaser Charles Edwards with his tour group at about the same time. The view is to the SW from I-70 east of Russell, Kansas.
Small wall cloud on the southern side of the storm as it splits near LaCross, Kansas. Outflow can be seen undercutting the storm updraft as well. The view is to the west.
Hail being observed near LaCross, Kansas with many stones at least an inch in size covering the ground. Chaser Don Sanderson's vehicle is in this picture, who was also chasing with Dan Shaw that day.
Another supercell develops near Saint John, Kansas late on June 15. This storm also produced very large hail, before evolving into a cluster of severe thunderstorms near Pratt, Kansas.
Chaser Dan Shaw's vehicle under an incredible display of mammatus clouds while wrapping up the chase north of Pratt, Kansas on SR 61 near dusk on June 15.


GALLERY FOR JUNE 16, 2017

June 16 was a chase day back up in Nebraska, and targeting an area around Norfolk to OíNeil. This was where a weak low, warm front, and dryline / pacific cold front would interact with a NW flow regime. In the left picture, the SPC has an enhanced risk in place as of 1630z, mainly for wind and hail, and only a 2% tornado probability as shown in the inset. This is also reflected by the mesoscale discussion 1055, where the aforementioned weak low and frontal features are outlined. To the right is the annotated visible satellite image for around 45z (the following day, which is late afternoon / early evening on June 16). Supercells have matured and are heading to the SE, and evolving into a destructive MCS (or even an MCC) containing XDW (eXtreme Damaging Winds) into SE Nebraska and eventually north-central Kansas.

Heading north on SR 14 in Nebraska towards Albion during the afternoon of June 16, 2017. A supercell looms over the horizon while passing through a work zone on the way to the target area near Norfolk.
Here is the view of the supercell storm from the south between Albion and Madison, Nebraska from along SR 32. The storm is tornado warned at the time, and the start of a long day and night of severe weather.
Developing wall cloud on the supercell storm northwest of Madison, Nebraska.
Large rotating wall cloud and supercell updraft just before getting undercut to the west of Madison, Nebraska. The view is to the west and northwest.
Brief "bird fart" tornado / gustnado under the rotating wall cloud to the west of Madison from along SR 121. The view is WNW.
An LP supercell was on-going southwest of the main activity to the west of Lincoln, Nebraska all the while. In this view, from near Columbus, Nebraska and looking southwest, the LP storm has split into two separate LP supercells.
Small funnel cloud forms on a wall cloud associated with the southern split of the LP storm west of Lincoln, Nebraska late in the afternoon of June 16. This is just prior to a derecho producing storm cluster racing in from the north catching up with it.
View of an intense HP supercell embedded in a derecho producing MCS of extreme damaging winds that will push across SE Nebraska and well into Kansas. The colors and lightning are impressive with the setting sun and cloud structure. This storm will produce winds exceeding 100 MPH.
Cloud to ground (CG) lightning strikes to the northwest of Beatrice, Nebraska as the storm was intensifying and producing 80 to 100 MPH wind gusts.
Another picture of the cloud to ground (CG) lightning strikes to the northwest of Beatrice. This storm had some of the most frequent lightning I ever seen in my life (at least 10 flashes per second)!
Numerous downed powerlines on a farm road to the west and northwest of Beatrice, Nebraska after dark on June 16. This was the only route to get into Beatrice, impossible without a 4x4.
Downed trees, flooding, and wind damage in Beatrice, Nebraska during the late evening of June 16.


GALLERY FOR JUNE 17, 2017

June 17 was another chase day with two distinct target areas, with each one having similar chase prospects. One was with extreme instability over central Kansas, and another over north-central to northeastern Missouri and southeast Iowa and into western Illinois. The latter had slightly better upper level support, as both targets were being merely glanced by the strong jet stream dynamics to the north. The 1630z SPC had a large area in enhanced risk, which contained these two target areas, and is shown to the left. In the middle is MCD 1074, showing the storms that developed in severe thunderstorm watch box 345, and how it pertains to my target area. To the right is the annotated visible satellite for around 45z (also UTC for the following day). In my target area is the ďtail endĒ supercell in that region, while back in Kansas, a severe MCS is evolving from supercells there. None of these produced any tornadoes.

View approaching a supercell storm near Memphis, Missouri late in the afternoon of June 17, 2017. The storm will soon become undercut by outflow, as many storms did days prior.
View of severe storm gust front to the west of Memphis, Missouri.
Another view of the storm gust front about 10 miles south of Memphis, Missouri. Despite being outflow dominant and undercut, the supercell storm is still producing hail up to baseball sized.
View of wall cloud and RFD region, still intact, after gust front passage and being undercut by the shallow layer of outflow air. The storm is still producing very large hail at the time.
Using my vehicle winch to clear a tree from a blocked roadway after storms passed through on June 17 in NE Missouri.


GALLERY FOR JUNE 18-26, 2017

June 18th to the 26th was either down days, travel days, or attempted chase days that wound up being a complete WASTE of time. On June 21 and 22, I attempted a final chase but that wound up being a "cap bust". Back in Chicago on the 22nd, I eventually made the trip back down to Florida, leaving Chicago on June 25, and arriving in South FL on the 26th. In the images above, the SPC products are shown, including the 1630z slight-risk outlook, and measly 2% tornado probabilities (down from 5% and eventually eliminated altogether on subsequent outlooks) for June 21. To the middle and right are the MCDs (mesoscale discussions) 1010 and 1013, respectively, well to my SW and far to my NE, with my area "capped" all afternoon and evening. Meanwhile, the best probabilities for tornadoes are along the northern Gulf coast, associated with (sub) tropical storm "Cindy" making landfall west of there. I was back in south Florida by June 26, and the sting of seeing tornadoes in Iowa on June 28 made this past week "hurt" that much more.

A small thunderstorm attempts to break through the strong cap to the southeast of Sioux Falls, SD during the late afternoon / evening of June 21, 2017. The area remained capped all day, with clear blue skies, and elevated storms to the far north over ND / western MN, or non-severe storms in far SW Nebraska. Basically I got a sunburn instead of seeing storms in the target area.
Impressive mid-level convective rolls streaming over southern Minnesota on June 22, 2017. This is associated with the southern edge of a powerful jet stream disturbance moving north of the area near the US / Canadian border. Unfortunately, this upper level support remained out of phase (well to the north) of the better low level moisture and instability (over Iowa) for severe storms.
Driving back from Chicago to Florida, crossing over the Louisville, Kentucky bridge over the Ohio River during the early afternoon of June 25.
View of a (totally harmless) strong thunderstorm and shelf cloud north of Gainesville, Florida while heading south on I-75 late in the day of June 26.


OTHER CHASES IN 2017 IN THE MIDWEST

This section is for any other chases and / or storm pictures taken in the central United States / Midwestern areas during 2017. These include any chases or observations of storms that were local chases (or trips lasting a single day), but not part of a dedicated / longer chase trip. This area is also UNDER CONSTRUCTION, so please keep an eye on this page for future updates.


DETAILED CHASE LOG FOR THIS SECTION (OTHER CHASES)

1). Jan 1, 0:00 PM - This is a TEMPLATE.

This concludes the chase log for the central United States and Midwest for ANY OTHER chases in 2017 not part of a special section (especially those for single-day "spot" chase trips). The summary includes a total of TBD observations. Out of the observations, there were TBD severe thunderstorms and TBD strong thunderstorm. Out of the thunderstorms, TBD possible tornadoe were observed. The main chase vehicle conducting these chases was a 2016 Jeep Wrangler / TBD. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.


GALLERY FOR JAN 1 (OTHER CHASES)

Details COMING SOON!


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