Fortunate to have off of work this day, I took advantage of this rather meager sfc low (only 1002mb) and chased. I had limited access to weather data this morning and afternoon, but thankfully my chase target looked fairly clear cut by 18Z. The warm front was located about 180 miles to my north and along with that were the best low-level helicities. Viewing the 12Z soundings for Springfield, MO and Lincoln, IL told me that the dry slot was advecting closer to the warm front near Lincoln. The dewpoints were only modest (upper 50s) at Lincoln, but theta-e values were nearing 325K at St. Louis and the dynamics would ensure convective initiation. As the dry slot worked in, clouds eroded and temperatures responded into the upper 70s in southern IL. My target was just south of Springfield, IL.

After leaving my apartment outside of St. Louis at 1pm, I was treated to a great display of cirrus streaks courtesy of the jet max aloft. Heading north on I-55, a distinct east-west line of broken, yet highly sheared TCu was visible to my north. I had a good feeling about this and knew it was very close to the warm front location. Upon stopping at a rest stop near Atwater a little over an hour later, I watched this zone of convection and soon my eyes were locked on an interesting sight well to the west. At first it looked like just another TCu, but when the mid-level clouds cleared a rocky updraft with a backsheared anvil was present! This was verified on the radar at the rest stop with a nice reflectivity pattern about 30 miles west of Springfield. The chase had now commenced! Tornado warnings were issued for this cell and I continued northward for the intercept. Unfortunately, this HP supercell blasted through Lincoln about 15 minutes before I arrived and left an 18 wheeler overturned right by the HWY 10 exit which I needed to take. Traffic was crawling along for at least 2 miles, but I did make it eastward into Lincoln and saw widespread minor damage/power outages (likely convective winds to blame). East of Lincoln, I deliberately fell under the wet RFD region of this supercell but thanks to a poor road configuration near Clinton, I never did make it in front of the beast. The highlights were some awesome outbound winds in the RFD gusting to at least 40mph, 1" hail in a nice hailshaft (see below), mammatus, and some vivid CGs. The supercell continued to the ENE but was laying such an extensive outflow boundary that the new convection quickly became linear. Behind this initial zone of activity was another nice convective explosion enhanced by the retrograding cold pool and the actual cold front further to the west. Though somewhat impressive, the sfc thermodynamics were limited for obvious reasons...but a meso did occur near the Decatur area on the southern end of this line. Altogether, a nice chase considering it's early April, but it still doesn't make up for my bust back on February 14 of this year northeast of Tulsa! Though it sure would have been nice to have been off of work the next day and chase in TX.  NOTE: The damage in Lincoln was attributed to a 70-100mph microburst; however a tornado occurred just west of the city prior to this wind.
 

Jet max cirrus above dry slot	Distant SVR Cb to the west	Bland looking HP tornadic supercell	View to the west
Nice hailshaft (note scud formation)	Mammatus	New convection in supercell's wake	Microburst damage in Lincoln

• 18Z theta-e analysis
• 18Z Sfc obs
• Lincoln NWS summary