This section is for storm chases done in the central (or even the western) United States during the year of 2008 that were not part of the main chase log (mainly for my home state of Florida) and also not part of any dedicated chase expeditions in 2008 (such as the one for May 19 through June 1). In addition to any dedicated chase "expedition" (that is where a 2-3 week "block" time was spent chasing at the mercy of whether or not the weather would co-operate), some "spot" chasing was done this year, where only major severe weather "setups" were chased. All chases in the central USA will be logged in this section. Here you should find many pictures of lightning, possible tornadoes, 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 plagiorize or copy this document to other sites for distribution.

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STORM CHASING - CENTRAL UNITED STATES - SPECIAL 2008 CHASE LOG

Be sure to check back this page often as all chases in 2008 in "Tornado Alley" and / or the Central USA will be logged in this section!

TABLE OF CONTENTS - CLICK TO GO TO PAGE

THIS IS CHASE SECTION ONE FOR 2008

Central USA Chase Expedition 2008 - Section TWO

Note: There were TWO chase log sections for the severe storm season of 2008! You are currently viewing the FIRST section, which includes storm chases in the central US during the season of 2008 (that is not part of the trip conducted from May 19 through June 1, 2008). To jump directly to the SECOND section, please click the link provided above.

ABOUT THIS CHASE LOG FOR THE MIDWEST

This is a chase log for any chases during 2008 in the Midwest and Central United States that were conducted as "spot" chases during or do not have a dedicated page for them. Each chase section within this area will have its own details and such for that particular chase. This area was set up in the winter / early spring of 2008 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 - REAL VIDEO FORMAT

"Super Tuesday" Killer-Tornado Outbreak Video - Feb 5, 2008 (TN)
 Severe Storm Chase Trip (April 8-11, 2008) in TX / AR
 Severe Storm Chase Trip (May 1-2, 2008) in KS / IL / WI
 Severe Storm Chase - June 22, 2008 (IN) - New!

CHASE FOR JANUARY 7, 2008

January 7, 2008 was an impromptu storm chase that was mainly focused on strong winds and lightning in the Chicagoland area near Interstates 94 and 55 in Cook county, Illinois. This was part of an extremely rare setup for tornadoes and severe thunderstorms for this far north at this time of the year. A low pressure system was moving northeastward across the midwest and temperatures up to 65 degrees reached the IL / WI border with dewpoints in the upper 50's. Even more interesting, this moisture boundary layer was deep while less than a week prior, the air mass was entirely arctic / Canadian with clear skies, blowing snow, and temperatures near 0 degrees F!

The storms were also developing in a region of high shear and became tornadic to the southwest, near SW Missouri and north along the warm front neat the WI / IL border. Storm mode was mostly line segments elsewhere, but intense ones. The storm predictions center had a large slight risk extending from southern lake Michigan into the deep south-central US. Ironically, tornado watch boxes, #1 and #2, the first two of 2008, were issued for central and northeastern Illinois, respectively. The line of storms passed through the Chicago area by evening, and I was able to head out and intercept my first sxevere storm of the season, as well is get some incredible video of lightning hitting the top spires of the sears tower. This was an entirely local chase since I was staying near I-80 and I-94 in Chicago for work at the time.

JANUARY 7 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN1-7IT CONSULTANT

DETAILED LOG FOR ALL CHASES

1). Jan 7, 6:00 PM - Indirect penetration of a severe thunderstorm in Cook County, Illinois to the southwest of downtown Chicago near Interstate 55. The storm was at the extreme northern portion of a line of strong and severe thunderstorms, unusual for this area at this time of the year. Conditions with this severe storm’s northern edge included heavy rains, winds near 50-MPH, small hail, and frequent lightning with some close hits. The storms were caused by a strong low pressure system, surface convergence, boundary interactions, and a strong upper-level low pressure area. Street flooding was onserved with this storm, and several direct hits of lightning to the Sear tower were also documented. A 2008 Ford Focus was used to chase the storms. Documentation was a camcorder. A tornado watch was also valid for this area until 9 PM CST.

This concludes the chase log for the chase trip on January 7, 2008. The summary includes a total of 1 severe thunderstorm. The main chase vehicle conducting this chase was a 2007 Ford Focus. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR JANUARY 7, 2008

The line of severe thunderstorms moves rapidly through and south of downtown Chicago (Cook county, Illinois). This severe storm, with winds over 50-MPH and small hail, was on the northern part of a large line of thunderstorms. In this picture, I am headed north on I-55 to find a place to stop and shoot lightning, which was very frequent.
With the camera fixed on the highest point in Chicago, the top (lightning rods) of one of the Sears Tower building spires, lightning hits. Note the unique and upward branching effect. This is because the lightning polarity is positive, common with winter thunderstorms due to higher quantities of ice crystals aloft. Image is a frame from video.
The same lightning bolt hitting the lightning rods atop the Sears Tower spires, but a second after. The main bolt becomes evident and the branching disappears. Image is a frame from video.
Some street flooding near Lansing, Illinois after the passeg of the squall line of strong and severe thunderstorms.

CHASE FOR FEBRUARY 4, 2008

February 4, 2008 was a really quick and unexpected storm chase that mainly was conducted along Interstate 65 in Lake and Newton Counties, Indiana to target a line of abnormally strong thunderstorms. Conditions at the surface were entirely winter like, with about 6 inches of snow on the ground from a snow-storm the previous evening, and temperatures 35-40 degrees with dense fog. The storm line was elevated above this cold surface layer with air parcels originating from the warmer low-level jet (850 MB flow), which was around 50 degrees. Basically checked radar at 8:30 PM CST to see the convective trend and left via I-80 east then I-65 south targeting the area in Indiana between Highways 2 and 114 (near Fair Oak).

After heading south on I-65, in dense fog, the line of storms was encountered just north of Fair Oak, Indiana. Conditions included strong winds and frequent lightning, which some semis blown into the median of I-65. Fog was mixed in with the strong winds of the thunderstorms, along with blinding lightning (reflecting off the snow-covered ground)! The chase was brief, and wrapped up with a return back along I-65 (turned around at Highway 114) then I-80 west to Chicago by 10:30 PM CST.

FEBRUARY 4 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN2-4IT CONSULTANT

DETAILED LOG FOR ALL CHASES

1). Feb 4, 9:30 PM - Penetration of strong thunderstorms along Interstate 65 near Fair Oak, Indiana southward to near Morocco (highway 114) from southern Lake County into northern Newton County. The storms were a portion of a multi-cell squall line of strong thunderstorms moving across the area, rather unseasonable for this time of the year. The thunderstorms contained very heavy rains, small hail, winds gusting over 50-MPH, and frequent lightning with close hits. Extremely dense fog was associated with the thunderstorm environment, and the ground was still snow-covered from a snow storm less than 24 hours earlier! Bad visibility caused accidents, and a semi-trailer was blown into trees in the median on I-65. A warm front and upper-level trough produced the storms. The storms were elevated and ahead of a surface warm-front to the south. A strong jet-stream was also present aloft. No surface heating was noted with this setup. A 2007 Ford Focus was used to chase the storms. Documentation was a camcorder. A severe thunderstorm watch was also valid for the area until 1 AM CST.

This concludes the chase log for the chase trip on February 4, 2008. The summary includes a total of 1 strong thunderstorm. The main chase vehicle conducting this chase was a 2007 Ford Focus. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR FEBRUARY 4, 2008

Here is a picture (frame from video) of a strong thunderstorm moving across Indiana near southern Lake county, Indiana on Interstate 65. In this picture, a cloud to ground (CG) lightning strike is to the right, but two things set this picture apart from an ordinary thunderstorm. First, the ground is covered with snow, from a snow storm that ended only 12 hours before the thunderstorm. Second is the fog, vety dense, making for an interesting effect with the lightning and snow pack. Temperatures in this elevated strong storm were only 35-40 degrees.
Very bad visibility in blinding rains, small hail, fog, and 50-MPH winds just north of Fair Oak in southern Lake county, Indiana on Interstate 65.

CHASE FOR FEBRUARY 5, 2008

February 5, 2008 was a "long-shot" and high-risk chase day involving a long drive to the target area (from Chicago, Illinois to near Memphis, Tennessee) and involved the interception of a few dangerous tornadic supercells. This system was responsible for the "Super Tuesday Outbreak" where tornadoes killed about 59 people. The chase began in the early morning of February 5 with a primary target area of Sikeston, MO where I-57 and I-55 meet, which was just south of a stationary / warm front. Forecasting also revealed a developing low pressure area what should move up this frontal zone providing adequate moisture and instability in the warm-sector. Meanwhile, an intense short-wave trough was ejecting into the central US, with a low-level 850 MB flow of 60 Knots from the SSW, then an 80-Knot 500 MB SW flow, and 300 MB over 100-Knots from the WSW, with strong di-fluence aloft near and south of the primary target area.

Left Chicago via I-80 then south on I-57 and was in the primary target of Sikeston, MO near I-57 and I-55 by early afternoon. Temperatures went from cold drizzle and 35-40 degrees to 65-70 degrees and partly sunny skies south of the boundary! Checked data in Sikeston and found the best possibility of severe weather was to be south of the area. At SPC, a high-risk was issued for the 16:30z outlook, with a frightening 30% hatched tornado probability, 40% hail, and 45% hatched damaging wind. The hatched meaning a significant severe weather event. By mid afternoon, a region of confluence showed on the visible satellite along the Mississippi River and an adjustment was made to head south on I-55 toward Memphis, Tennessee. A mesoscale discussion (MCD) and subsequent PDS (Particularly Dangerous Situation) tornado watch went up with the adjusted target area in the northern half of it.

The trip south on I-55 was on, with another stop for data near Hayti, Arkansas to confirm the confluence axis was indeed firing storms. A weak and high-based cell was encountered near Haydi, with more vigorous convection farther south. This convection was linear in nature, and quickly raced to the northeast. Upon entering the Memphis area, and crossing the Mississippi River along I-40 into the north side of town, the first severe storm was encountered. This storm was to produce the first significant tornado northeast of town and the chase track passed close to its wall cloud during its development to supercell mode. The storms were HP in nature, and bad visibility / traffic was a big problem. This first storm was abandoned with a re-position south to near I-240 and I-55 to view the storm and tornadic section from a distance.

Two more significant supercells developed after the initial storm, and were farther southwest, and both moved over and near the Memphis International Airport. The first had strong rotation and a wall cloud, while the second was to be one of the most significant supercell storms. The second storm skirted the south side of the city and quickly intensified to produce a large, long-track tornado that was to take lives and leave destruction in its path well to the northeast. The chase came within a half of a mile of this tornado, and the parent supercell core was penetrated in a hasty retreat to get out of its path. Visibility, traffic, and rapid storm motion was a major problem, but a glimpse of the tornado was observed just at sundown from its northeast.

Damage was extensive as this storm and tornado moved rapidly NE, especially near and along Winchester road. The storm was to continue NE, in darkness, to produce more tornadoes with damage and fatalities to and beyond Jackson, TN, almost 80 miles away! A brief damage survey was done along with a radio interview with Scott Roberts with Virtual News Center. The chase was wrapped up in Memphis at about 7 PM CST, with the long return going back up I-55 towards Sikeston. Another supercell, ahead of a squall line with hail, high winds, and a possible tornado, was observed again just south of the I-55 / I-57 junction at 9 PM CST. The return continued back north into Illinois along I-57, where numerous semis were noted blown-over in the median and side of the interstate. The drive back to Chicago was completed at 2:30 AM CST on early February 6. Total mileage was 1,119 miles.

FEBRUARY 5 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN2-5IT CONSULTANT

The participants below are not from the "Sky-Chaser" chase team. These people often actively participate in my storm research and documentation efforts and deserve appreciation for their great help and severe weather expertise. Jeff Gammons and Tony Laubach below provided now-casting and updates and were of great help during this chase.
CHASER NAMEHOME CITYCALLSIGNOCCUPATION
JEFF GAMMONSOKEECHOBEE, FLKG4PGAPHOTOGRAPHER
TONY LAUBACHLITTLETON, COKC0ONLSTUDENT

FORECASTING AND TARGET AREA - FEB 5

In the three images above, the Storm Prediction Center (SPC) day-one outlook products appear for the impressive 30% hatched tornado (left) and the 30% hail outlooks (middle), and the 45% hatched wind for the 16:30z time. This was all constituting a high-risk in the SPC convective outlooks, with the strong-wording a significant severe weather event (such as a tornado outbreak) was to (or expected to) occur.

The diagram above shows the chase map for this setup based on my forecasted target area(s). The initial and final targets are shown, as well as my "ferry" path from Chicago to those areas. You can also compare this to what the Storm Predictions Center (SPC) forecasted in the diagram before this chase map as well.

STORM DETAILS AND RADAR IMAGERY - FEB 5

The annotated diagram above shows three images. The left image is a composite of the Mesoscale Discussion #0169 (issued by the Storm Prediction Center) with an overlay of the PDS (Particularly Dangerous Situation) watch-box area for Tornado Watch #37. In the middle picture, also from SPC, a typical "outbreak" pattern is depicted in their storm reports product. More interesting is that at least 68 confirmed reports of tornadoes, depicted by red dots, have been confirmed. The blue and green dots represent MANY severe wind and hail events, respectively. A black triangle or black square denotes an extreme hail (2" or larger) or extreme wind (65-Knots and higher) event, respectively. To the right is an infrared satellite image and inset base-reflectivity radar image during the major portion of the outbreak over western Tennessee. Note that the really dangerous supercell storms were discrete updraft cells developing AHEAD of the squall line to the west.

DETAILED LOG FOR ALL CHASES

1). Feb 5, 4:30 PM - Penetration and observation of a very severe and tornadic thunderstorm on the north side of Memphis in Shelby County, Tennessee along and south of Interstate 240 and 55. The storm was an HP supercell storm developing on the southern portion of a broken line of strong and severe thunderstorms. This storm also produced a significant tornado to the northeast of Memphis and this was observed from a distance from just northwest of Memphis International Airport. Near the core of this storm, 50 MPH winds, very heavy rains, frequent lightning, and small hail was encountered. A large, blocky wall cloud was found in the rain-free base of the storm when headed south on I-240. The storms were caused by a strong low-pressure trough, both surface and aloft, slight surface heating, boundary interactions in a highly-sheared environment. A 2007 Ford Focus was used to chase the storms. Documentation was still digital photos and a camcorder. A PDS (Particularly Dangerous Situation) tornado watch was also valid for this area until 12 AM CST.

2). Feb 5, 5:30 PM - Indirect penetration and observation of a severe thunderstorm near Capleville and east of Memphis International Airport in Shelby County, Tennessee near Lamar Avenue (Highway 78). The storm was a small supercell storm that was northeast of a stronger and more intense storm to its southwest. The storm had frequent lightning and a very large rotating wall cloud. It did not produce a tornado in the immediate area. The storms were caused by a strong low-pressure trough, both surface and aloft, slight surface heating, boundary interactions in a highly-sheared environment. A 2007 Ford Focus was used to chase the storms. Documentation was still digital photos and a camcorder. A PDS (Particularly Dangerous Situation) tornado watch was also valid for this area until 12 AM CST.

3). Feb 5, 6:30 PM - Direct penetration and observation of an extremely severe and dangerous tornadic thunderstorm near the intersection of Airways Blvd and I-240 in Shelby County, Tennessee and points south and east. This storm was a significant supercell storm that was to produce a long track and destructive tornado from southwest of Memphis International Airport then east and northeast near Germantown and eventually as far as Jackson. Observing this storm was very difficult due to visibility (because it was at dusk and in a populated area) but a brief glimpse of the tornado (a large bowl-shaped lowering on its SW side nearly to the ground) was attained. The core of the storm hit, with the tornado passing just 1/2 mile to my south, and winds (core or RFD) gusted from 70-80 MPH, frequent lightning with close hits, sideways and torrential rains, and hail 1" to isolated golfball-sized was encountered. A hasty retreat was made down Airways road south then east on Democrat road north of the airport, then SE Lamar (Highway 78). The RFD blasted to 70-MPH in rapidly clearing air and a large lowering (tornado) was visible to the east with power-flashes (very poor contrast) when making an eastward turn on Winchester road. Extensive damage to residences, a shopping mall, and numerous businesses was observed, especially where Winchester road and Hickory Hill roads meet. Debris was scattered across the street, and many powerlines / trees were down. This damage path was at least 1/2 mile wide and extended SW to NE with areas of more or lesser damage. Power was also knocked out along this path. The tornado also caused more damage and deaths during its long track to the NE at over 60-MPH. A quick radio interview report and damage survey was also conducted after this storm. The storms were caused by a strong low-pressure trough, both surface and aloft, slight surface heating, boundary interactions in a highly-sheared environment. A 2007 Ford Focus was used to chase the storms. Documentation was a camcorder. A PDS (Particularly Dangerous Situation) tornado watch was also valid for this area until 12 AM CST.

4). Feb 5, 9:00 PM - Penetration and observation of a severe thunderstorm and possible tornado observation to the southeast of Sikeston in New Madrid County, Missouri along Interstate 55 and south and along Interstate 57 and eastward through Charleston and towards Cairo, Illinois. The storm was an HP supercell storm developing ahead of a multi-cell line of strong and severe thunderstorms associated with the cold front of the approaching low-pressure area. The storm had frequent lightning with some close hits, hail to 3/4", torrential rains, and winds to 60-MPH. A large cone shaped lowering, illuminated by lightning, was noted south of this storm cell before encountering precipitation when about 5 miles south of Sikeston on I-55 (looking NNE). The storms were caused by a strong low-pressure trough, both surface and aloft, and approaching cold front in a highly-sheared environment. A 2007 Ford Focus was used to chase the storms. Documentation was a camcorder. A PDS (Particularly Dangerous Situation) tornado watch was also valid for this area until 12 AM CST.

This concludes the chase log for the chase trip on February 5, 2008. The summary includes a total of 4 severe thunderstorms with 3 possible tornadoes, two of which are confirmed, and one of which was a killer tornado. The main chase vehicle conducting all chases was a 2007 Ford Focus. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR FEBRUARY 5, 2008

The long drive south to the target area along Interstate 57 was mainly in 35-40 degree temperatures with fog and drizzle. In the extreme southern tip of Illinois, and crossing into Missouri, the warm sector was encountered. Looking south in this picture, the NE to SW oriented frontal boundary, with partly sunny skies to the south can be seen. A temperature increase from 40 degrees F to 70 degrees F also existed heading south across this boundary.
This picture shows a small and highly-sheared towering cumulus trying to develop southeast of Hayti, Missouri. This was on the northern portion of another differential heating boundary that was in place from here southward, and was to be a key player in storm development later. The tower goes up, but does not last long as the shear quickly topples it over.
Headed south on I-55 from Missouri into Arkansas, a multi-cell line of strong and severe thunderstorms rapidly develops along a differential boundary / confluence axis nearly parallel to the Mississippi river to the east. The target is not these storms, but the southern portion of this storm complex. Note the mesocyclone denoted by the slight banding in the mid-levels of the updraft column, flared out base, and weak RFD "notch" in the large cumulonimbus from the center of the picture and to the left.
The southern end of this line of sever thunderstorms develops a tail-end "Charley" type supercell. This large storm was one of the first to develop north and west of the Memphis, Tennessee area. The view is to the south from a distance of about 30 miles.
Interesting cloud formations in the back-side of the first developing HP supercell to the north of Memphis, Tennessee. The game plan is to take I-40 and divert to the north of the storm's updraft and then south to view the updraft base.
Here is a view of a large, rotating wall cloud just northeast of downtown Memphis, Tennessee. This storm was rapidly intensifying and was to produce one of the first tornadoes in the area. The view is to the south towards the "bear's cage" of the storm on I-55 / I-240.
Here is a view of one of the first supercell storms from an overpass just northwest of Memphis International Airport looking northward. The RFD clear slot is evident and "lowerings" (tornado) on the ground behind it just to the left of the darker precipitation core. This picture was taken just when a large multi-vortex tornado was ocurring just NE of Memphis, TN.
A large wall cloud passes just south of Memphis International Airport near Lamar Avenue (Highway 78) and just north of Capleville in Shelby County, TN. This storm was a supercell storm which did not produce a tornado, but was part of the supercell outbreak across the area.
Interesting inflow tail (aka "Beavers Tail") extending from the south to the north (view is to the east from an overpass along I-240) into a supercell storm (the same one that produced the rotating wall cloud in the previous picture above).
This is a view of the anvil blowoff (top-right), updraft tower (center), and flanking-line (lower left) of the to-be devastating supercell storm that would cause death and destruction south and east of Memphis. The view is from an intersection south of I-240 and Highway 78 (Lamar Avenue). Keep in mind that this chase was near dusk, in a populated area, and during rush hour. Note the clear-cut anvil edge to the upper-left.
Looking west at the tornadic supercell's updraft base from near I-240 and Airways Blvd, a large lowering (wall cloud / developing tornado) can be seen to the west and southwest (center of the picture). This is the only glimpse of the approaching disaster because of horrible urban terrain and poor-lighting / contrast at dusk. The storm core is to the right, and coming right at me.
The southern core of the supercell passes over as I quickly make a hasty retreat to blast back east and get ahead of the storm. I am between the tornado, now tearing across then southeast of the Memphis International Airport 1/2 mile to my south, and HP supercell core (with hail to baseball sized) to my north. Winds are from the north and gusting 70-80 MPH with hail 1" to golfball sized. Unfortunately, there was no way to get ahead of a storm moving east and northeast at over 65-MPH.
Here is an annotaged image taken just minutes after the tornado passed over the Winchester / Hickory Hill areas southeast of Memphis. The view is to the east and northeast and the contrast is absolutely horrible, so I'll have to describe what is being looked at. Power is knocked out, and a damaged building can barely be seen to the lower left, with power poles dowm. The updraft base / flanking line of the rapidly departing supercell can be seen to the right. From the center to the left, the large lowering is a portion of the large tornado moving off to the northeast. The lighter shades from the upper-left is dusk twilight trickling through the RFD "clear slot" behind the supercell core.
With power out and a long SW to NE oriented damage path, many roads became strewn with both power poles, tree debris, and damaged building debris. This is near the Winchester mall, where people were trapped under a collapsed roof.
Many emergency / fire rescue vehicles flood the Memphis streets and points east as search and rescue begins after the tornadoes. As darkness falls, tornadoes continue to the east causing more deaths and destruction into central Tennessee. Daylight on February 6 (the next day) was to reveal the true horror of this outbreak.

CALIFORNIA STORMS ON MARCH 15, 2008

March 15, 2008 was NOT a regular chase day, as I happened to be in Central California with best friend of mine at the time. However, a region of low pressure aloft, with attendant vort-max (DVA) and extremely low temperatures (-34 degrees at 500 mb), allowed cold-core convection to develop along and behind a weak Pacific cold front. The most intense storms observed occurred with the daytime heating with surface temperatures around 65 degrees and a dewpoint of about 55 degrees. Winds were west and northwest at the surface, changing to north aloft. A small convective element in Contra Costa county, near Concord, produced small hail to pea sized and a bried funnel cloud. Meanwhile, the storm predictions center out-looked the central California area with a 5% hail probability. Some hail reports were also reported from this area. The upper-level low pressure system moved south and east of the area causing more severe weather in the central US a few days later. Seeing storms like this in this part of the western United States is unusual, and takes a very powerful low pressure system aloft to cause any convection in an otherwise stable cool Pacific air mass.

MARCH 15 OBSERVATION MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN3-15IT CONSULTANT
TONY ISUNNYVALE, CA???3-15CONTRACTOR

SOUNDING DATA FOR MARCH 15

The image above shows a sounding taken from OAK (Oakland, California) on March 15, 2008 during the early afternoon (0z on March 16 for UTC). Note the lapse rate (red plotted line with rapidly decreasing temperatures with altitude), starting at near +15 degrees C at ground level and reaching a bitter -34 degrees C at 500 MB (roughly 18,000 feet). Also, in this post-frontal environment, we see NW surface winds veer with height as we procede upwards in the atmosphere, with a stiff northerly wind aloft. Also notable is the height of the tropopause, a mere 400 MB (24,000 feet) marking the start of the stratosphere above the "tropopause gap", a lowering of the tropopause height above upper-air lows and jet streams. The tropopause is normally 35,000 feet or higher (rarely below 250 MB). The CAPE is just under 500, denoting mild instability, but with such cold air and low pressure aloft, post-frontal convection is likely. We see absolutely no capping or inversions of any kind in this sounding (outside of the tropopause itself) and the LCL and CCL are nearly equal at about 880 MB (roughly 4,500 feet). Normally a low level inversion is present in California, but in this case, it's not there.

DETAILED LOG FOR THIS STORM OBSERVATION

1). Mar 15, 4:30 PM - Observation and penetration of a strong thunderstorm, and attendant funnel cloud, along Highway 4 in Contra Costa County, California. The storm was a cold-core thunderstorm developing in a cool Pacific air mass under a region of very cold air aloft. Small hail (pea sized), 30+ MPH winds, and heavy rains were encountered with this small storm. A brief funnel was noted on the northwestern side of the storm during peak intensity to the northeast of Concord, California. The funnel did not touch down. Conditions causing the storms were modest surface heating, a strong low-pressure area aloft (steep lapse rates), and boundary / orographic interactions. A 2007 Dodge Calibre (rental) was used to observe the storms. Documentation was digital stills and digital video.

This concludes the observations log for the storms in central California on March 15, 2008. The summary includes a total of 1 strong thunderstorm and 1 funnel cloud. The main chase vehicle conducting this chase was a 2007 Dodge Calibre (rental). This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR MARCH 15, 2008

This is a storm south of Highway 4 in Contra Costa County, California with some rather interesting storm structure (slight rotation). A hail shaft is clearly visible to the left in this picture. Note the interesting updraft base to the right on the northwest side of the storm. Motion was to the southeast and the view here is to the SSW. The foot hills of Mount Diablo can be seen east of Concord in the background.
A small funnel cloud develops on the updraft side of the small storm northeast of Concord, California as we look west along Highway 4. The funnel lasted about a minute and did not touch down.
Looking east from Concord, California, the storm moves to the southeast and over the mountains and into the central valley. Mount Diablo, over 4,500 feet high, is the large mountain grazing the storm's high base, and is probably receiving wet snow and hail from the storm. The afternoon sun angle allows good contrast and a rainbow.
This is a picture of the small hail (pea sized) hitting ther windshield while passing one of many intense cold-core storms. The hail was very soft, almost like baby snowballs. The low freezing level (less than 850 MB) and steep lapse rates allowed the storms to produce hail like this.

CHASE FOR MARCH 31, 2008

March 31 was a chase day taken as a large deviation into the south-central US from a drive from Chicago, IL to south Florida as part of the end of a 3-month long computer programming project. The storm chase began after analyzing data and targeting a potential for severe storms from SW Missouri (initial target was the Springfield area) and points south and southwest. Eastern Oklahoma presented the best severe storm dynamics, but with a 9 AM departure from Chicago, that was a bit far. Headed down highway 55 through Saint Louis, Missouri by 1 PM CDT and continued southwest along I-44 for the Springfield target. The target area was reached by about 4 PM CDT and convection / storms were on-going and in the form of a powerful squall line of intense storms. One intense cell was penetrated near Springfield with strong winds and damage noted along I-44 (roof blown off building and debris strewn across parts of the highway).

After reaching Springfield, the chase track turned south and southwest along Highway 65 into Arkansas, attempting to target the environment ahead of the line / cluster of storms. Another severe storm was encountered near Clinton, Arkansas near dusk after changing a spare tire. It became clear the more potent storms were in Eastern Oklahoma at the "tail-end" side of the line, and nothing major in the way of tornadoes occurred (except for the earlier storm near Springfield, Missouri). The chase ended with a track back east along Interstate 40 through Fort Smith and the night was spent in Memphis, Tennessee. The tire was also replaced the following morning (April 1) in Memphis as well, and the drive to Florida continued after that with another night spent on the final leg of the trip in Orlando, Florida. I returned in Miramar on the morning of April 2.

The chase was not bad, but a bit frustrating. Considering a deviation from a long drive I had to do anyway, it was not that bad. The atmosphere put out a squall line but little in the way of the discrete supercell storms preferred by storm chasers. The SPC (Storm Predictions Center) out-looked a moderate risk on the 16:30z products for March 31 with probabilities of a 15% hatched tornado, 45% hatched hail, and 30% damaging wind threat. Many of these verified, but not to the extent as expected. A total of 510 miles of "deviation" were set for this chase, in addition to the 1,357 miles that would have otherwise been driven from Chicago to southern Florida. The conditions causing the storm were a frontal boundary and strong low-pressure system (with strong upper-level winds / forcing).

MARCH 31 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN3-31IT CONSULTANT

SPC PRODUCTS AND CHASE TRACK MAP

The image above shows the SPC (Storm Predictions Center) products as well as the chase track for this setup. The main map is the storm reports for March 31, 2008. Each green, blue, and red dot represents a large hail, damaging wind, and tornado report, respectively. Exceptionally large hail (over 2") and extreme wind (over 65 Knots) is denoted by a black triangle and black square, respectively. The blue line is the entire path driven from Chicago to southern Florida including the deviation for this chase. The dashed blue line would be the routine drive back to Florida had I not been chasing.

DETAILED LOG FOR ALL CHASES

1). Mar 31, 4:30 PM - Penetration of very severe (or possibly tornadic) thunderstorms to the northeast of Springfield, Missouri along Interstate 44 in Webster County. The storms were a portion of a multicell cluster / line of strong and severe thunderstorms. The cell penetrated was an HP supercell / bow segment within the line of storms that contained wind gusts near 70-MPH and hail up to dime-sized. Torrential rains and frequent lightning was also noted with this storm. Debris was observed across Interstate 44 along with trees / poles down and a roof ripped off a building. This storm was the same storm that caused tornado-like damage to the north of Springfield. The actual tornado was not observed, but a cyclonic motion was noted with the storm. The storm was caused by a low pressure system and strong upper-level disturbance. Documentation was digital video and stills. A 2007 Ford Focus was used to chase the storms. A tornado watch also was in effect for the area until 9 PM CDT.

2). Mar 31, 6:30 PM - Penetration another severe thunderstorm in Van Buren County, Arkansas near Clinton along Highway 65. The severe storm was part of a multicell line of strong and severe thunderstorms. Heavy rains, frequent lightning, small hail, and winds gusting over 60-MPH were observed with this storm. The storm was caused by a low pressure system and strong upper-level disturbance. A 2007 Ford Focus was used to chase the storms. A tornado watch also was in effect for the area until 9 PM CDT.

This concludes the observations log for the storms in Missouri and Arkansas on March 31, 2008. The summary includes a total of 2 severe thunderstormS (one of which was most likely the cause of tornado damage near Springfield, Missouri). The main chase vehicle conducting this chase was a 2007 Ford Focus. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR MARCH 31, 2008

Passing through Saint Louis and into Missouri from Illinois just after 1 PM and crossing the Mississippi river via I-55 (connects to I-44). This chase was also fantastic chance to test and validate two great new additions to my storm chasing "toolbox". I was able to get AT&T wireless mobile broadband vie their new 3G (Sierra) USB card and sign up with Swift WX for data. These two worked very well together and cell / data signal was seldom lost, even in very remote areas of the Ozark Mountains. In this picture, we can see the squall line as well as the SCIT displays (Storm Cell ID and Tracking) denoting hail and / or storm rotation. Swift WX also allows location tracking (other chasers can be seen) as well as GPS interfacing showing your location, the storm, and roads all in one integrated package!
Interesting convective rolls (light and dark bands) in the low-level stratocumulus deck denote extreme wind shear ahead of the storm cluster / line in central Missouri. Unfortunately, lack of sunshine (sufficient diurnal heating) kept instability modest.
Here is a view of the gust front of the severe storm near Springfield, Missouri. This storm had a possible tornado as well as a history of producing wind damage. Winds at this time were gusting near 70-MPH.
One of those chasing "moments" ... Flat tire from a piece of metal in the roadway north of Clinton, Arkansas along highway 65. This did not stop the chase, as I was able to put on the spare and have the tire replaced the following day.

CHASE TRIP FOR APRIL 8-11, 2008

In the annotated map above, the total path taken from April 8 through April 11 including air travel, the target area(s), and chase routes can be seen. The starting (and ending) point for this chase trip was Fort Lauderdale, Florida where a flight from Fort Lauderdale, Florida to Dallas, Texas was taken on April 8 (with a return on April 11). The main target area was on April 9 in west-central Texas (near Abilene along the I-20 corridor) and another (tentative) target eastward into Arkansas expected the following day (April 10). The main focus by far was April 9 in Texas. A total of 1,450 miles was spent driving around Texas, Oklahoma, and Arkansas from April 8 through April 11 (April 9 and 10 being the actual chase days). The target areas are circled, and the "road" chases appear as blue lines. The flight to (and from) Florida and Texas appears as a green line. Any red "X" denotes actual chases or observations.

CHASE SUMMARY FOR APRIL 8 THROUGH APRIL 11, 2008

This was a "mini chase expedition" responding to a potent severe weather setup in central Texas and points eastward from April 8 through April 11, 2008. The "go" or "no go" decision was made on April 6 and 7 when forecast models all agreed on lee cyclogenesis and a powerful front / dryline setup on April 9, with activity shifting east on April 10 (with April 9 being the best day). I was able to get an airline ticket from Fort Lauderdale, FL to Dallas, TX at a reasonable price along with a car rental for the same period (April 8 to April 11). Meanwhile, SPC (Storm Prediction Center) showed a moderate risk of severe storms 2-3 days out with April 9 being the "best" chance for chasing. On the evening of April 8, I arrived in Dallas after a stop-over in Houston, picked up the rental vehicle, and spent the night in Dallas near I-35 East. According to forecasting, as well as SPC's moderate-risk outlook, a tentative target stretching from Childress to San Angelo, Texas was agreed upon, so there was no rush getting into the target area.

On April 9, another forecast was done, and a warm-front was draped across Texas from WSW to ENE near the I-20 corridor. Meanwhile, a strong trough / shortwave was present over New Mexico, with diffluent and strong jet-stream winds expected to rotate into western Texas by afternoon. A strong instability axis (CAPE over 2500) and shear axis (helicity over 500) intersected an area close to Abilene, Texas. After speaking to Tony Laubach and Verne carson, in Amarillo, TX at the time, we also agreed that near Abilene was a great target area. At the Storm Prediction Center (SPC), a 15% hatched tornado area, 45% hatched hail, and 35% hatched wind outlook constituted a high-end moderate risk for the same region near Abilene about a 100 mile radius or so (a "hatched" outlook means the chance of strong tornadoes, hail over 2", and extreme winds over 65 knots within 25 miles of a point in the outlook area)! I left Dallas and headed north to Denton, Texas on I-35 with a westward track along highway 380 through Decatur. Headed south along highway 281 from Jacksboro and into Mineral Wells by lunch time. The final leg into Abilene was by highway 180, then highway 16, then westward on I-20.

I reached Abilene by about 2 PM CDT and obtained fuel plus a new power inverter at a truck-stop there. By this time, Tony and Verne met up with Tim Samaras at Sweetwater, about 25 minutes to the west on I-20. I left Abilene along highway 277 and stopped to make sure my equipment (radio, inverter, and laptop) was set up. The 55 degree drizzle and fog rapidly gave way to partly sunny skies and 80+ degrees just south of Abilene denoting passage / crossing of the warm-front boundary. At this time (3 PM or so) the SPC issued PDS (Particularly Dangerous Situation) tornado watch box # 178 valid until 8 PM CDT for the area in response to MD (Mesoscale Discussion # 607). A data check confirmed this area was ready to see convective initiation since the dryline boundary was still well to the west, a differential boundary between a stable and unstable (well-mixed) boundary layer to the west was present, both intersecting the warm front. Sure enough, a thunderstorm cell fired to the south of Sweetwater and west of Nolan near highway 277 and 126. This cell was encountered, and showed the start of some supercell characteristics, and allowed to pass to my east (while keeping an eye on it). This storm also contained small hail.

This developing shower / storm was to be the big storm, and the only best storm of the day! I met up with Verne carson, Tony Laubach, and Tim Samaras near I-20 and highway 70 and notified them about the developing storm. The well-defined frontal boundary was right along I-20, with the "fog bank" visible to the north, and partly cloudy skies to the south. My group and I watched the storms, including the cell that I saw initiate, along with a few other storms that seemed to weaken quickly. The original storm showed the best possibilities, and a tornado (TVS) was indicated by radar on it, so we grouped up and headed east on I-20 to catch it. We encountered the storm near Tye, TX along I-20, where a rotating wall cloud / funnels, intense RFD, and some small dusty "spinups" were noted. We headed north on highway 707 towards Hodges and Anson to encounter a large funnel and dust (quite possibly tornado #1). The storm appeared to rapidly wrap-up at this point, with very intense rotation, while evolving to an HP supercell and eventually weakening somewhat. Another weaker mesocyclone to the south appeared to "merge" with this cell. Large hail (golfball and larger) and frequent lightning was also encountered on highway 707.

We left this storm and planned on following it along I-20 as it started taking more of an ENE motion rather than NE as id did originally. We stopped for fuel near Baird and continued east on I-20 to Cisco, then to highway 6, then north on highway 183. The supercell now violently intensified, showing an incredible SCIT (Severe Cell ID and Tracking) of 198 knots gate-to-gate shear with a flying eagle and couplet on the Dyess AFB radar site. The storm motion also changed from ENE to ESE at this point. Its position was just southwest of Breckenridge, Texas and we were headed north on highway 183 towards it (by about 20 miles away at 5:30 pm CDT) after being slightly delayed by a freight train in Cisco. We encountered the SW side of Breckenridge, with an RFD shelf cloud in front and possible tornado to the NE of our position. This may have been Tornado #3, developing in the new mesocyclone of the storm to the east, while #2 was not visible but responsible for extensive damage in Breckenridge. A semi truck was blown over and lying across highway 183, and many power poles were snapped, along with trees down, and roofs torn off some buildings. The damage path appeared to be at least a half-mile wide, with opposing damage direction (such as snapped poles leaning opposite directions) on each side of the damage swath.

We passed into downtown Breckenridge and headed east on highway 180. More damage was encountered on the east side of town, with poles snapped, powerlines down, roofs torn off buildings, and structural damage. We stopped to document as well as help some locals move debris from the road, as well as making sure no one was hurt. Later analysis of the video taken of the damage near highway 67 and 180 clearly shows the rope tornado stage, to the NE, and most likely from tornado #2 that caused much of the damage in Breckenridge. After the supercell storm got east of Breckenridge, it underwent some drastic evolutions. The storm crossed the differential boundary and its inflow began ingesting the cooler stable air to the east. Inflow was very impressive east of the storm near highway 180 near Palo Pinto, with gusts over 60 MPH. The gate-to-gate shear relaxed significantly from 120 knots down to 50-60 knots and the storm went entirely HP, with a warm advection wing to its southeast. This storm was followed to Mineral Wells along highway 180 then north on 281. Impressive 60-80 MPH winds were noted south of the area of rotation with this storm. At this time, Tony Laubach and Verne carson broke off of the chase, as I continued north (with Tim Samaras) on 281 towards 380 to head back east.

The supercell continued moving northeast, but never intensified again, instead, it just got weaker and weaker until it lost its identity northeast of Pilot Point / Denton, TX and well east of I-35. This was roughly at 9:30 PM. From initiation to weakening, the single supercell lasted more than 6 hours. Tim Samaras and his crew and myself spent the night in Denison, Texas with the next-days chase prospects in mind (possibly OK / AR). A potent squall line developed late at night (April 9-10) and moved through by 4 AM or so, with violent winds and frequent lightning. The rapid passage of this squall line was to determine the chase prospects for April 10, and a target of eastern Arkansas was sought by myself. Tim Samaras and his group decided not to chase, and needed to be back in Colorado by April 11. I left Denison and headed north on highway 69 / 75 to Durant, Oklahoma, then east on highway 70 into Arkansas to continue the chasing on my "free day" of April 10.

I continued east through Broken Bow, Oklahoma and across the border into De Queen, Arkansas by about 11 AM CDT. According to SPC, a similar setup was in place across the eastern part of the state, with 15% hatched tornado probabilities and a moderate risk ahead of a weakening squall line from earlier (this SHOULD allow discrete supercell development). I pretty much followed the winding mountain road of highway 70 then 270 into Pine Bluff, and finally highway 65 to the target area. SPC issued tornado watch #189 and an MD noting the weakening squall line and potential for strong tornadoes with any supercell developing in eastern Arkansas. Watch 193 was also issued extending the tornado threat farther east as well. A weak outflow boundary was noted east of Dumas, AR and I headed north on highway 165 to keep an eye on the small cells developing along this shear axis (winds were west to its west, and strong out of the south to its east). One weak storm did produce some small funnels, but the main upper-air support (lift) remained well to the west of this area, where some elevated strong storms developed. I decided to call off the chase by about 7 PM CDT as the boundary crossed the Mississippi River to my east, and headed back north along Highway 1 then 49 to Interstate 40. Before doing so, I was able to document severe flooding in some communities near Marvell and Aubrey, Arkansas.

The attention shifted to wrapping up the chasing and head back to the southwest along Interstate 40 through the elevated showers and across the dryline / pacific front (clear skies were met again east of Little Rock, AR) then take I-30 out of Little Rock to make it back to Dallas, Texas by 11:30 PM CDT for the night. I was able to pack up my equipment, and after spending the night in Dallas, returned the rental and flew back to Fort Lauderdale, Florida on a 2 PM flight. This long (and fun) chase went very well, with 3 tornadoes intercepted on April 9 and flooding / storms on April 10. The total distance driven was about 1,450 miles over the 4-day trip.

APRIL 8 TO APRIL 11 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN4-8 TO 4-11IT CONSULTANT

The participants below are not from the "Sky-Chaser" chase team. These people often actively participate in my storm research and documentation efforts and deserve appreciation for their great help and severe weather expertise.
CHASER NAMEHOME CITYCALLSIGNOCCUPATION
TIM SAMARASDENVER, CON/ASCIENTIST / ENGINEER
TONY LAUBACHLITTLETON, COKC0ONLSTUDENT
VERNE CARSONDENVER, COKB0ZCQIT

FORECASTING AND TARGET AREA - APRIL 9

In the three images above, the setup and effects on April 9, 2008 are portrayed. To the far left is an enhanced water-vapor image of an unusually strong upper-level low (500 MB) over the American Rocky Mountains. The most notable feature in the water-vapor satellite image is the dry air "slot" working its way from Mexico and into SW Texas. Ahead of that feature is both strong winds and divergent air-flow aloft, which enhances thunderstorm intensity as well as aiding in lee-cyclogenesis. The middle picture is MCD (mesoscale discussion) 0607 placed over the region in Texas where a warm-front boundary and shear / instability axis are present, and points to a high probability of tornadic supercell formation. A PDS (Particularly Dangerous Situation) tornado watch (WW # 178) was issued for the same area. To the right is the actual storm reports for April 9, where a blue dot represents severe winds, a green dot represents large hail, and each red dot represents a reported tornado. Some of the red "dots" in west-central Texas were the tornadoes we were able to intercept, including one causing extensive damage near Breckenridge, Texas. The black squares and black delta-triangles represent extreme winds (over 65 knots) and giant hail (2" or larger), respectively.

STORM RADAR / SATELLITE IMAGERY - APRIL 9

The annotated diagram above shows two radar images from the Dyess Air Force base radar site (near Abilene, Texas) plus a visible satellite image from around the same time over Texas. The image to the left shows radar base reflectivity and the middle image shows the storm velocity (Doppler based). In the reflectivity image on the left, a supercell storm is un-mistakable, with a well-defined "hook" echo about the time it was affecting Breckenridge, Texas. This distinct signature is sometimes called a "flying eagle" because of its resemblence to a bird shape (wings and tail to right, with the "hook" the birds head / beak to the left). In the middle image, a well-defined velocity couplet denotes an area of rotation with the same supercell storm. This supercell was most intense at this time and weakened there-after, however, it had an exceptionally long track, reaching extreme NE Texas by midnight (7 hours later)! The right image is a visible satellite image of the supercell storm. Note the supercell storm in the visible satellite image to the right, denoted by the anvil (upwards of 55,000 feet) spreading off to the NE with the diffluent upper-airflow. The cell is "anchored" on the intersection of at least two boundaries, one a very defined warm / stationary front extending from the WSW to ENE, and the other a north-to-south oriented differential boundary separating a warm well-mixed air mass from a more stable (stratiform clouds) air mass to the east.

FORECASTING AND TARGET AREA - APRIL 10

The three images above show the setup and storm report details, provided by the Storm Prediction Center (SPC) for April 10, 2008. To the left is the tornado probability in an a moderate-risk outlook, with a 15% hatched outlook in eastern portions of Arkansas. The middle image is a tornado watch-box (watch #193) issued by SPC for the area the chasing was done in for April 10. The image to the right is for the actual storm reports for April 10. Despite high expectations, the true storm reports were confined to a squall line (damaging winds, hail, and isolated / weak tornadoes) that pushed through the area earlier, leaving little storm activity in the "hot" areas in Arkansas. This day was a "free" day after a fantastic prior chase day, so I decided to attempt a chase that day anyway.

DETAILED LOG ALL CHASES

1). April 9, 5:30 PM - Interception and observation of an extremely severe and tornadic thunderstorm near Breckenridge, Texas and near Highway 183 and 180 in Stephens County, Texas. The storm was a violent supercell thunderstorm that had a very long track, initiating near Nolan, Texas (near Highway 277 south of Sweetwater) and tracking well to the east and northeast before finally weakening near Collinsville (at least 6 hours later and over 200 miles to the NE of its point of initiation)! The storm was the most intense for a short time as it tracked from near Tye, Texas to points past Breckenridge. This storm produced at least 3 tornadoes during this early stage in its life, and as it was in classic supercell mode (after that it weakened and evolved to HP). 3 tornadoes were observed, including the end-stage of the destructive second tornado that affected Breckenridge. Torrential rains, winds gusting well over 70-MPH, frequent lightning, and golfball-sized hail (or larger) was also encountered with this storm. Damage observed was in Breckenridge, and included an overturned semi-truck, power poles snapped, trees uprooted, and buildings / houses destroyed (or having their roofs torn off). Luckily, no one was hurt in Breckenridge, but I did stop to help out / clear debris. The storm was caused by a warm / stationary front, boundary / dryline interactions, surface heating, intense wind shear, and a strong low pressure system / trough. Documentation was still digital pictures and HD video. A PDS (Particularly Dangerous Situation) tornado watch was also valid for the affected area until 8 PM CDT. A 2008 Kia (rental) was used to chase the storms.

2). April 10, 4:30 PM - Observation of a small but possibly severe thunderstorm in Desha County, Arkansas near Highway 165 and to the northeast of Dumas. This was a small storm that developed along a shear-axis (boundary) and produced some brief funnels on its updraft base. The core of this cell was not intercepted and no damage was observed, except for severe river flooding (from many other storms earlier that day in a squall line) which inundated some homes and farms in the area. The storm was caused by boundary interactions, surface heating, wind shear, and a strong low pressure system / trough. Documentation was still digital pictures and HD video. A tornado watch was also valid for the affected area until 11 PM CDT. A 2008 Kia (rental) was used to chase the storms.

This concludes the Chase Log for the Texas, Oklahoma, and Arkansas area from April 8 through April 11, 2008. The summary includes a total of 2 severe thunderstorms, one of which produced at least 3 tornadoes. A total of 3 tornadoes were observed with one of the storms, all confirmed. The main chase vehicle conducting all chases was a 2008 Kia (Rental). This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR APRIL 9, 2008

Here is a view headed souhwest towards the target area of Abilene, Texas along highway 180. The weather here is cloudy and foggy, with rain and cool drizzle because I am still north of the warm-front boundary, which is still near Interstate 20 and 40-50 miles away.
One of the first storms to initiate along and south the warm-front boundary near Sweetwater and Abilene. This storm, in the center of the picture, will eventually be the long track (and destructive) supercell of the day. The anvil to the upper left is from a weakening and elevated storm north of the warm-front to our west. The view is ENE.
Tim Samaras and Tony Laubach watch a developing supercell near Tye, Texas off I-20 after clearing a tumble-week that was stuck under the front of his van.
Impressive RFD clear slot develops (left side of picture) and funnel cloud can be seen to the right as the supercell storm intensifies near Tye, Texas. The view is to the northwest.
Rapidly rotating wall cloud and possible tornado (tornado #1) near highway 707 and noth of Tye, Texas. The funnel / tornado is between the center and right side of the picture. Other storm chasers reported a dust swirl associated with this feature confirming a tornado (the dust is not visible in this picture). The view is to the northwest.
Intense RFD clear slot and funnel associated with the same developing supercell near highway 707. This is still possibly on the ground. The view is to the west.
Golfball-sized hail pounds highway 707 as a smaller mesocyclone to the south of the Tye supercell storm merges with it and the intense precipitation core passes overhead.
While blasting north on Highway 183 out of Cisco, this incredible supercell storm (with the classic "flying eagle" radar image) bears down on the unfortunate town of Breckenridge, Texas. Shear values of almost 200 knots showing nicely via the Dyess AFB radar site! Radar and tracking (using GPS) provided by SwiftWX software and data service provided by AT&T's Sierra 3G mobile broadband USB package.
Semi-truck overturned on highway 183 just south of Breckenridge, Texas. The driver was not hurt. This was part of a large damage path which contained power poles and trees snapped, as well as some buildings severely damaged or destroyed.
This is a view, looking NE along the damage path at a possible tornado (and possibly a second tornado that struck Breckenridge and points east). The tornado is just above the foreground and in the center of the picture. Other chasers east of Breckenridge were reporting a large and dusty tornado at this time, looking in the opposite direction. Intense RFD and clear "slot" can be seen to the left.
Some more damage on the eastern side of Breckenridge, texas near highway 180 and 67. Some homes and buildings were severely damaged or destroyed, and power poles were snapped. The view here is to the east (not the backside of the new mesocyclone to the right-center of this cyclic supercell).
In this picture, caught by accident, the un-mistakable rope stage of the first Breckenridge tornado can be seen in the center of this picture (from a video surveying the damage near highways 180 and 67). Some airborne dust and debris, just above the man walking, and left of the tornado, can also be seen. This is the old mesocyclone of the supercell, with the new mesocyclone resulting in the new tornado to the east of town (shown earlier in one of the pictures above). The view is NNE.

GALLERY FOR APRIL 10, 2008

A small funnel develops on the rain-free base of this small severe storm in eastern Arkansas (northeast of Dumas). Despite high severe weather expectations, the "ingredients" for a severe weather outbreak did not "phase up" as expected.
Severe flooding was the biggst impact in this area, near Marvell and Aubrey, Arkansas. This home is severely flooded by rising river waters as helpless residents wade through the flood.
Flooded trailer park / camp ground near Aubrey, Arkansas.
Interesting cloud formations east of Little Rock, Arkansas and along I-40. The lack of "phasing", where the surface features and upper-level features "line-up" for a severe weather outbreak, caused less than expected severe weather this day. Well behind the surface boundary and instability axis, the area of upper-level vorticity (DVA and upper-lift) makes its mark with elevated showers and clouds denoting extreme turbulence aloft. The clouds take on a "mammatus" like appearance because of the turbulence.
The mid-level dry air slot of the now large storm system to the northwest over the central USA is preceded by a dryline / Pacific front. The clouds and moisture appear to suddenly stop near the leading edge of this boundary (dry-punch). The view is to the west.

ARIAL VIEW OF WEATHER / SUPERCELL STORMS

This picture was taken after departing Houston, Texas on a Boeing 737 at an altitude of about 20,000 feet on April 8 at about 6:15 PM CDT while en-route to Dallas. The view is to the south and southeast, and bands of clouds called horizontal convective rolls (HCR's) can be seen far below in the boundary layer. These clouds are caused by rising air in a moist boundary layer that is capped with stronger winds, often from a different (usually veered) direction aloft. The cloud bands develop along rising air while the "spaces" between them are sinking air, and align parallel to the low-level winds, forming a horizontal "aspect roll" (vortex couplet). These cloud formations are often found in environments where moisture and directional wind shear (horizontal rotation) prevades the low-levels of the atmosphere.
This picture was taken during the arrival into Dallas, Texas after connecting through Houston on a Boeing 737 at an altitude of about 25,000 feet on April 8 at about 6:40 PM CDT. The plane actually descended to get under the anvil of the storms, and turbulence was moderate for a short time. This was most likely the frontal genesis of the warm front boundary that was to be such a big issue for producing tornadoes on April 9. The storms here are severe, and eventually produced two tornadoes about 50 miles south of the Dallas-Fort Worth area. Note the "split" developing between the two storms to the lower left, in a DOWNWARD looking point of view!
This picture was taken from a Boeing 737 leaving a Houston, Texas connection to Fort Lauderdale, Florida on the afternoon of April 11 (roughly 6 PM EDT) at about 39,000 feet over the Gulf of Mexico and well off the Louisiana / Mississippi coastline. Looking to the NNW, the un-mistakable view of a supercell storm looms over the horizon. Based on SPC's storm reports, this storm was responsible for a tornado, violent winds (over 80-MPH), and hail at least baseball sized (2.75") in Louisiana and Mississippi.

CHASE TRIP FOR APRIL 29 TO MAY 5, 2008

In the annotated map above, the total path taken from April 29 (including the actual chasing done on May 1 through May 2) to May 5 is shown, including air travel, the target area(s), and chase routes. The starting (and ending) point for this chase trip was Fort Lauderdale, Florida where a flight from Fort Lauderdale, Florida to Kansas City, Missouri was taken on April 29 (with a return on May 5). There were a few tentative target areas for this trip, mainly focusing on May 1 and May 2, with the SE Kansas target being the most promising. The arrival day (April 29) and April 30 were not chase days. A remote possibility of a chase in SW Nebraska on April 30 was discouraged as lack of moisture return was a problem that day. The main target (Arkansas) on May 2 was reluctantly abandoned for a target area farther north (Illinois and Wisconsin). After wrapping up chasing on May 2, time was spent in Chicago (vacation) until return on May 5. A total of 2,005 miles was spent during April 29 through May 2 with May 1 and 2 being the actual chase days. The target areas are circled (lighter shades show aborted targets), and the "road" chases appear as blue lines. The flight to (and from) Florida appears as a green line. Any red "X" denotes actual chases or observations.

CHASE SUMMARY FOR APRIL 29 THROUGH MAY 5, 2008

This was both a chase trip and vacation combined, with the chasing focused on a significant severe weather setup from Kansas and eastward, with May 1-2 being the best chase prospects, according to computer forecasting models 4-5 days prior. The decision to tackle this setup was made about 3 days before the actual departure on April 29, and utilized some "reward points" for my frequent-flyer program, so not much was at stake. I was most interested in May 1, where a classic dryline setup, and lee cyclogenesis would set the state for a severe event in Kansas. I was able to get tickets to fly from Fort Lauderdale, Florida to Kansas City, Missouri (with a stop in Tampa, Florida) and car rental from the same destination. The original plan was to fly out on April 29, head west to NW Kansas / SW Nebraska (for a slight and very conditional probability of storms there) on April 30, then chase the "big setup" in Kansas on May 1. May 2 was also to be a chase day farther east, but was not pin-pointable at the time. From May 3-5, the plan was to head to Chicago after chasing as no storms were expected those days, and spending vacation Tim there, then returning to Kansas City early on May 5, and returning to Florida that same day from Kansas City (airport).

After arriving in Kansas City on April 29 and getting the car rental, I headed west on I-70 to spend the night in Abilene, Kansas. On April 30, I headed west to Hays, KS anticipating that the intense 500 MB trough, over N California the day before, would begin affecting the high plains after clearing the Rocky Mountains (via a lee trough and subsequent lee cyclogenesis). Moisture return was the big problem with this prospect, so the target (SW Nebraska) was abandoned and some sight-seeing near highways 183 and 136 (Harlen County Lake in Nebraska) was done instead. The forecast for the following day was still promising, so a track back along 136 east to highway 75, then south through Holton, NE, and eventually into Lawrence, Kansas via highway 24 to spend the night.

May 1 was to be the main chase day for this trip. The original target area, after much forecasting, was to be near Chanute, Kansas, which was about 80 miles south on highway 59. Two other target areas existed as well, one near Sioux City, Iowa (way to the north) and another in central Oklahoma. All looked good, with a departing low to the north, and more cyclogenesis expected to the southwest. Dewpoints finally began re-bounding, and reached the mid 50's. Meanwhile, a strong south / southeast wind was blowing in response to the developing low and winds aloft began increasing. By mid day, a dryline boundary began establishing itself near Wichita. Another main concern was the cap (inversion) over both the Kansas and Oklahoma targets. This forecast was not an easy one to say the least, but I wanted to stick with my original plan of SE Kansas. I waited in Chanute for a few hours waiting for the signs of the cap breaking, while communicating with fellow chasers Tony Laubach and Tim Samaras in Wichita at the time.

With signs that the cap was about to break, I continued west out of Chanute at about 4 PM on highway 39. Meanwhile, the Storm Prediction Center (SPC) had the area I was in outlooked at a moderate risk of severe storms, with 5% tornado, 45% severe hail, and 30% severe wind probability. The hail outlook was hatched meaning significant (2" or larger) was possible. Another 5% tornado outlook was for the farther north area in SW Iowa. SPC issued Mesoscale Discussion (MD) 758 and then tornado watch box 244 including SE Kansas by 5:30 PM, valid until 1 AM CDT. After heading west on highway 39 / 400, the dryline boundary was encountered. Dewpoint dropped from 57 to 48 and a line of towering cumulus was noted to my west. I dropped south on highway 99 to near Howard. This is where a large towering cumulus field was noted to the south. In mere minutes, the cap breached and this mass of agitated cumulus quickly and explosively developed into a supercell storm near highway 160 SW of Fredonia by 6 PM. This storm began by producing large hail, some as large as tennis balls.

The storm moved northeast, eventually affecting areas in Wilson County near highways 160 and 75 (Fredonia, Benedict, and Altoona). The storm produced several wall clouds, then funnels / possible tornadoes. There were MANY chasers on this storm, including the ROTATE team, Doppler On Wheels (DOW) truck and new Tornado Intercept Vehicle (TIV II), and many others. A tornado was observed with this storm while it cycled through an intense HP stage near the intersection of highways 39 and 75 at about 8 PM. The storm was continually followed until about 10 PM past Chanute and into Allen county. The storm weakened afterwards. The chase was wrapped up on this supercell and I tracked back north on Highway 59 and 169 to spend the night in Ottawa (where Tony Laubach and Tim Samaras were also to stay after back-tracking to Wichita to pick up a rental vehicle). I was able to shoot some lightning still images from along highway 31 between highways 59 and 169 along the way. I arrived in Ottawa, KS where an intense squall line raced through about midnight, with winds gusting over 70 MPH. Tim and Tony decided to spend the night in Wichita. The plan was to head into SE Missouri (and possibly S Illinois) on May 2 as the intensifying system would make an even higher tornado threat there (SPC was already forecasting a 15% hatched probability).

After spending the night in Ottawa, I got up very early anticipating a long drive east. I was rather disgusted to see that the squall line, which pretty much erases any storm chasing prospects in its wake due to the cool air pool, has pushed all the way across to the MO / IL border (near Saint Louis). Tim Samaras and Tony Laubach, who were going to chase with me, decided to call it off. I decided to continue east, passing through Kansas City by 8:30 AM, and east on I-70 making Saint Louis by 11:30 AM. Saint Louis was "decision time", should I take my chances going south, to E Arkansas, still 4 hours away, or just make my way north to northern Illinois? The target area for May 2 was not only "hosed" by the cool pool in the squall lines wake, but now confined to an area in eastern Arkansas, parts of west Tennessee, and NW Mississippi. It became apparent that with on-going convection and the area now being too far south, it would be both impossible and impractical to continue south (via I-270 then I-55), so that target was abandoned. Attention shifted to the north, to near eastern Iowa, NW Illinois, and SW Wisconsin. A small area of warmer air was in place there, and a strong occluding low (over Iowa) with great upper-air support (strong winds, cold air aloft, 500 MB DVA) above it.

I got east of Saint Louis and headed NORTH on I-55 instead of south, crossing the Mississippi River and into Illinois. The squall line was far enough east of the area to allow clearing and (hopefully) heating of the boundary layer air. Sure enough, the Storm Prediction Center issued a new outlook for the northern (new) target, and had a 10% probability of tornadoes. Subsequently, MCD 778 and tornado watch box 252 was issued at 4:30 PM CDT for the area and points north (valid until 10 PM). Tim and Tony also considered chasing this setup as well, as they needed to go to Minneapolis on May 3 anyway. With this seeming to be a promising cold-core setup, I headed up I-55 to Springfield, IL then took I-74 through Peoria and north to I-88. Much towering cumulus was encountered in this region, with a strangely-oriented cold-front / shear axis extending from NW to SE and a warm front ahead of that extending WNW to ESE. Surface winds ahead of the warm front were SE, but S ahead of the cold front, and SW behind that, so there was little room for "backed" winds. Highway 78 was taken north of I-88. Two things were noted. First, the warm front spawned some small "mini supercell-like" cells that were highly sheared and visible to my north, but did not develop any farther. Second, a cluster of strong storms developed to my west near Stockton, IL at the point where the warm front and cold front intersect.

The developing storm was observed while crossing into Wisconsin from Warren, IL and produced strong winds and small hail near Gratiot, WI. It began acquiring some supercell characteristics, with a small RFD clear area, and wall cloud / small funnels. After that, the storm quickly became linear and weakened as the cold front and warm front, now both oriented NW to SE, occluded near Argyle, WI. The chase was wrapped up with a track east to highway 15, then I-39 to I-90 (toll) to make my way towards my planned stay in the Chicago area. This pretty much wrapped up my chasing, and started my short get-away in the windy city. Meanwhile, the original southern target, that was fouled by the cool pool and abandoned because of lack of interest in chasing in Arkansas (trees, rivers, squall lines with little or no development ahead of them - That's my experience at least), became the prolific tornado producer ;-(

The remaining time was spent in Chicago until my return on May 5. The original plan was to leave on the early morning of May 5 and drive back to Kansas City (about 8 hours) for my trip back to Florida. With gas prices so high and my connection (from Kansas City to Florida) happening to be in Midway (Chicago's smaller airport), I decided to pay a little extra on the rental and return the car in Midway on the evening of May 5 and take the connection (simply not get on the plane in Kansas City). I arrived back in Fort Lauderdale, Florida during the late evening of May 5.

APRIL 29 TO MAY 5 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN4-29 TO 5-5IT CONSULTANT

FORECASTING AND TARGET AREA - MAY 1

In the three images above, the setup and effects on May 1, 2008 are portrayed. To the far left is the Storm Prediction Center (SPC) outlook for 1630z (about 11:30 AM CDT). A moderate risk area is outlooked with SE Kansas being the main focus. Note the other areas that had storms (SW Iowa and Oklahoma) are only outlooked in slight-risk. In the middle image, the Mesoscale Discussion (MD) 758 is shown, with a great surface diagram showing the dryline, fronts, and wind fields in the pre-storm environment in the central USA. To the right is the actual storm reports for May 1, where a blue dot represents severe winds, a green dot represents large hail, and each red dot represents a reported tornado. Some of the red "dots" in SE Kansas were the tornadoes I was able to intercept. The black squares and black delta-triangles represent extreme winds (over 65 knots) and giant hail (2" or larger), respectively.

FORECASTING AND TARGET AREA - MAY 2

The three images above show the setup and storm report details for May 2, provided by the Storm Prediction Center (SPC). To the left is the tornado probability, with a 15% hatched outlook in SE portions of Arkansas (in a moderate-risk) and another 10% area near the IL / IA border (slight-risk). The annotations in the outlook diagram point to the original (abandoned) target area as well as the new one to the north. The original target was planned MUCH farther north than what is shown because the stable air left by the squall line. Originally, the 15% hatched tornado outlook extended well into Illinois. The middle image is the Mesoscale Discussion (MD) 778 issued for the northern area, clearly showing the cold and warm fronts, oriented more NW to SE, about to occlude, with a narrow window of storm prospects (and tornadoes) in (and ahead) of that narrow warm sector. The image to the right is for the actual storm reports for May 2. Note that despite the cold air behind the squall line pushing so far south, storms and tornadoes were still reported ahead of the system, especially in SE Arkansas, and the south-central states. The northern area, although promising at first, did not do a whole lot.

DETAILED LOG ALL CHASES

1). May 1, 8:00 PM - Interception and observation of an extremely severe and tornadic thunderstorm from near Howard / Moline, Kansas and points northeast through Chanute in Wilson County. The storm was followed from its point of initiation at about 6 PM to past Allen County at about 10 PM. The storm also produced a multi-vortex tornado, inwhich at least one suction vortex was observed on the ground with debris near the intersection of Highway 75 and Highway 39. The storm was a supercell thunderstorm, and evolved between classic and HP (high precipitation) modes. Numerous funnel clouds / possible additional brief tornadoes were also observed with this storm. The storm also produced frequent lightning, torrential rains, winds to 65-MPH, and hail up to tennis-ball sized (2.25"). No damage was observed as most tornadoes, hail, and winds occurred over rural areas of Wilson and Allen counties. The storm was caused by boundary / dryline interactions, surface heating, intense wind shear, and a strong low pressure system / trough. Documentation was still digital pictures and HD video. A tornado watch was also valid for the affected area until 1 AM CDT. A 2008 Dodge Calibre (rental) was used to chase the storms.

2). May 2, 12:00 AM - Observation of a severe thunderstorm near I-35 at the Days Inn motel in Franklin county in Ottawa, Kansas. The storm was a bowed-out line segment of severe thunderstorms, and produced winds gusting over 70-MPH. Frequent lightning, torrential rains, and pea to dime-sized hail was also observed with this storm. The storm caused some wind damage and knocked out power in some areas. The storm was caused by a strong cold front, upper trough (wind shear), and a strong low pressure system. Documentation was HD video. A tornado watch was also valid for the affected area until 1 AM CDT. A 2008 Dodge Calibre (rental) was used to chase the storms.

3). May 2, 6:00 PM - Observation and penetration of a strong to severe thunderstorm near Gratiot, Wisconsin and highway 78 in Lafayette County. The storm was a multicell storm but briefly acquired supercell characteristics before evolving to a line-segment. The storm produced small hail, very heavy rains, frequent lightning, and winds gusting near 55-MPH. A wall cloud and RFD (rear flank downdraft) was also noted on this storm before weakening. The storm was caused by an occluding cold and warm front, cold-core low pressure system, surface heating, and upper-level low (differential vorticity / cold air aloft). Documentation was still digital pictures and HD video. A tornado watch was also valid for the affected area until 10 PM CDT. A 2008 Dodge Calibre (rental) was used to chase the storms.

This concludes the Chase Log for the May 1 through May 2, 2008 in Kansas, Illinois, and Wisconsin. The summary includes a total of 3 severe thunderstorms, one of which produced at least 1 tornado. A total of at least 1 tornado were observed with one of the storms, one confirmed. The main chase vehicle conducting all chases was a 2008 Dodge Calibre (Rental). This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR MAY 1, 2008

Here is a picture of myself, working my laptop and equipment. I am connecting to the internet (via wireless 3G) to check data and forecasting products while waiting in the first target area of Chanute, Kansas.
Looking at the dryline from Howard, Kansas, which is moving in from the west, a line of cumulus develops along it. In this picture, the dryline boundary stretches from left to right along the lower portion of the picture. The highly-sheared towering cumulus (center) will reach the LFC (level of free convection) above the cap and explosively develop into a supercell (this one did so in LESS than 10 minutes). The view is to the WNW from the "moist" side of the dryline.
This is a picture of the roadway, near Fredonia in Warren County, Kansas, after the supercell core passed overhead. The hail stones laying in the road and on the ground were as big as tennis balls (about 2.25 inches).
The Warren County storm gets more organized, and a wall cloud forms, with these small funnels.
Here is a view looking SSW and upwards at the Warren County supercell main updraft. A sheer, striated vertical wall to the right denotes powerful, rotating updraft. The striated pattern is sometimes called a "barber pole" updraft. Speeds in this updraft can exceed 150-MPH. Note the impressive anvil towards the top of the picture. The distant supercell (lower left) in the picture is over Oklahoma and also produced a tornado.
An intense cloud to ground (CG) lightning strike occurs on the forward flank of the supercell storm in Warren County, Kansas. Note the wall cloud (center) and RFD shelf cloud to the left.
Several notable storm chasers and their vehicles can be seen in Warren County, Kansas near Altoona. The Doppler On Wheels (DOW) is to the left, the new Tornado Intercept Vehicle (TIV II) in the middle, and storm "scout" vehicle to the right. Josh Wurman and Sean Casey are the brilliant researchers working in these vehicles.
This is a view of the supercell storm in Warren County, Kansas as it was beginning to evolve to HP (high precipitation) mode. In this view, we see a large wall cloud (view is to the NW) and developing RFD slot to the left. To the right, a funnel / possible tornado can be seen.
Here is a picture showing the traffic jam of storm chase vehicles, comprised of both amateurs and funded scientists, that can jam an otherwise rarely traveled rural road. The supercell storm acts as a "beacon", attracting chasers from miles around.
This is the supercell in HP mode about 5 miles south of the intersection of highways 39 and 75 (looking north on 75). The notch of the storm is to the left side of the picture, and an RFD core (or "blob") of heavy precipitation is obscuring the view of a possible tornado. Note the inflow "beavers tail" in the background and near the ground, extending from right to left. I knew this storm was wrapping up (intensifying), so I blasted north to get a better look at it.
Here is a closer view of the wet RFD, which is actually the southern part of the "hook" of the storm. A tornado is inside the "bears cage" of the storm, and is not visible as the rain and hail block the view of it from this vantage point. The tornado inside would be behind the grey rain, and to the left of the center of this picture. My goal is to get past the rain "hook" and look to the west into the notch to see the tornado, which is EXTREMELY dangerous on HP supercells like this.
This is one of the tornadoes that touched down, and was actually a sub-vortex in a larger, broader circulation deep within the notch (or "Bears Cage") of the HP supercell storm. This was near highway 75 and 39 intersection in Warren County, Kansas. Falling rain and hail make the contrast poor, and no one else chasing this supercell probably even knew this tornado was in there!
This is a picture of a cloud to ground (CG) lightning strike on the backside of the thunderstorm cluster in SE Kansas after the last supercell storm weakened.

GALLERY FOR MAY 2, 2008

This is a picture of myself driving and passing through and around Saint Louis, Missouri to Interstate 55 in Illinois to head to northern target instead of southern (unreachable) one. The Gateway Arch can be seen from I-55 looking west in Illinois after crossing the Mississippi river.
Some small LP / mini-supercell (low-topped) type storms go up along the warm-front near the Illinois / Wisconsin border as low pressure and cold air aloft (cold core) approaches from the west. These small storms did not grow very big, and soon dissapated after this picture was taken.
This is the rain-free base and small scud tag / funnels developing west of Warren, Illinois and is associated with the approach of the cold-core system and occluding fronts.
Interesting rear-flank downdraft (RFD) feature on one of the cells as it moves into and near Gratiot, Wisconsin. Note the wall cloud behind the clear-slot (sun is peeking through the downdraft "hole").
As the cold front and warm front occlude, the storm cluster quicky becomes linear (outflow dominant). The backside has some pretty structure, especially with the afternoon sun hitting the back of the shelf cloud / gust front.

QUICK CHASE FOR JUNE 22, 2008

June 22, 2008 was a really quick and unexpected storm chase that mainly was conducted near and along Highway 10 to the south of Interstate 80 near Pulaski County, Indiana. This storm chase was conducted strictly as a "fun chase" as I just happened to be in the Chicago area and close to the region where the storms developed. The conditions in place included an upper-level disturbance (short-wave rotating about the southern end of a disturbance over the great Lakes) and a region of surface confluence. Mid to upper level winds were strong, but surface winds were light, so hail and wind were the main threats targeted with any storm observed. The storm prediction center also has a large area of slight risk outlooked, with northern Indiana included in the region. Probabilities were a 2% or negligable for the tornado threat, but a 30% hail and 30% damaging wind existed over the region from central Illinois to north-central Indiana. Mesoscale discussion (MCD) #1517 was also issued for the region, with north-central indiana included in it (no watch was issued).

This unexpected chase began with a friend of mine from chicago, after having lunch in Lansing, Illinois. Rock-hard and impressive convection was noted to the southeast of the intersection of Interstate 65 and Interstate 80 by about 2 PM. My friend wanted to see what a "storm chase" was like, so we went for it. We continued east on I-80, then south on Highway 2 to Highway 10, where a small supercell storm was encountered near Winamac by about 3 PM in Pulaski county, Indiana. The storm had a persistant wall cloud, frequent lightning, and large hail. The storm peaked out by about 3 PM and weakened / evolved to an MCS afterwards. The quick-chase was finished by about 4 PM with a drive back to Chicago (to return to FL later that evening).

JUNE 22 CHASE MAIN PARTICIPANTS

CHASER NAMEHOME CITYCALLSIGNCHASE DATESOCCUPATION
CHRIS COLLURAMIRAMAR, FLKG4PJN6-22IT CONSULTANT
MIKE MENDOZACHICAGO, ILN/A6-22ARCHITECT

DETAILED LOG FOR ALL CHASES

1). June 22, 3:00 PM - Penetration of a very severe thunderstorm in Pulawski County, Indiana near Highway 10 and Winamac. The storm was a small supercell storm developing at the southern end of a multicell cluster of strong and severe thunderstorms. The thunderstorm contained very heavy rain, large hail to the size of golf-balls, winds gusting near 60-MPH, and frequent lightning. The larger hail covered the ground at times, and downed tree limbs were noted in the street. Conditions causing the storms were an upper trough, surface heating, weak surface trough, and lake-breeze boundary (from Lake Michigan to the north). Documentation was still digital pictures and a camcorder. A 2007 Chrysler Sebring (rental) was used in this storm chase. A best friend (curious about storm chasing and living in Chicago) accompanied me on this storm chase.

This concludes the chase log for the chase trip on June 22, 2008. The summary includes a total of 1 severe thunderstorm. This information was prepared exclusively for the National Weather service and the team of Skywarn storm spotters.

GALLERY FOR JUNE 22, 2008

Here is a picture of an explosively developing supercell storm south of Interstate 80 in north-central Indiana (viewed from eastern Lake county). The storm has developed a rock hard anvl at this point. Picture taken by friend / fellow chaser Mike Mendoza.
This is a picture of the updraft base of the storm. The storm, despite light lower-level winds, appears highly sheared because of the strong upper-level flow (bulk-shear of 40 knots+ at and above 500 MB) associated with the short-wave trough moving across the Great Lakes. Updraft base is rather high, but well developed.
This is a picture of the wall clous associated with this supercell storm near Pulawski county and Highway 10 (near Winamac). This storm DID contain weak rotation, and a powerful updraft. Hail to golfball sized was starting after this picture was taken.
This small supercell storm produced a lot of hail. In this picture, taken by Mike Mendoza (chasing with me), hail to marble sized (with isolated golfball pieces) is on the ground and in the roadway (Pulawski county). Note the tree limb laying in the road.

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