"Surprise" mini severe weather outbreak in IA/IL/I

[PurdueWx80]

Earlier outlooks had slight risk to the north but they are down into central portions of IL/IN now. Looks like a weak wave has developed on the front in SE IA and there is a nice sharp delineation between very warm and humid air to the south of the front/outflow boundary, with cooler/drier air to the north. The boundary extends from Bloomington, IN to ILX to Burlington, IA. Winds have actually backed around to the E and SE ahead of the low, so low-level helicities are up to 350. With ample CAPE, vertical shear on the order of 40-50 kt and fairly low LCL's (although not perfect), could be some tornadoes, especially along the pseduo-warm front. Excellent turning with height up to 500 mb to allow for supercell development, and low wet-bulbs could mean large hail. Actually, I see there are already several golfball size hail reports from central IL, and a few tornado warnings in progress. Could possibly organize into MCS after dark, as cold pool builds behind squall line in IA.

[wx247]

Here are the current watches...

[PurdueWx80]

Awesome radar image from ILX weather service office showing supercell with hook echo west of Peoria. Appears to be riding the differential heating boundary/front.