18z Euro was very impressive for tomorrow and probably worthy of a MDT risk. Gives ample time to destabilize with 300+ m2/s2 0-1 km SRH becoming common along a 50 kt LLJ over SE IA, NE MO, and far W IL by 21z. Signal is for a discrete/semi-discrete band of cells along the arcing Pacific front/dryline with better lapse rates thanks to CAA aloft closer to the primary upper low.
There are a number of larger synoptic N MO/IA events that looks like this one at 500 mb (5/27/1995, 4/8/1999, 3/31/2023, 4/11/2001 amongst them), and the dryslot in the mid levels as 700-500 mb, which is absolutely paramount for these types of events, looks pretty potent. I also noticed that most of the CAMs, despite different evolutions, ended up with robust cells with strong UH across some portion of the region, both at 12z and 18z.