4/22/08 FCST: IL/IA/MO/AR/OK/TX

[John Farley]

Surprised nobody has started a thread for Tuesday by now. WRF/NAM shows CAPE of 2000 just east of the STL area by 0Z, though the shear is somewhat ahead of/out of phase with the best instability. Still, with decent instability and southeast winds for much of the day, there would seem to be some potential in this area. The STL NWS and local mets have been mentioning the possibility of severe WX in the area on Tuesday for a few days now, though SPC is still holding off on issuing a categorical slight risk. At the least, though, I think it bears watching, and I am hoping for a possible local chase day on Tuesday.

 

[Chris Lott]

Some of the forecast soundings in C. TX. are showing very high amounts of CAPE in excess of 4000 j/kg tomorrow, however shear doesn't look that great. Given the instability however, I wouldn't be surprised to see some good hailers come out of this with the approach of a weak frontal boundary. Given the instability that will be in place, I wouldn't be surprised to see a repeat of last weeks event over parts of North Texas. I wouldn't be shocked if I'm way off on this, but I see a possibility there.

 

[John Farley]

The lack of model continuity continues. The instability, which was gone on this morning's WRF in my main area of interest due to its proximity, the MO/IL area, is back, with CAPE of up to 3000 in the Ozarks. Very little wind shear there or anywhere else, though, and a complete lack of upper wind over the MO area. That is better way down the line in central TX along the dryline, but in that area, capping could be an issue, as the WRF does not break out much of anything in the way of precip in that area. If this model run verifies - highly uncertain given the lack of run-to-run consistency - I would expect some strong storms over the Ozarks in central to southern MO and maybe NW AR - but given the lack of shear, it looks like a lot of multi-cell pulse stuff with little chance for supercells. If the cap can be broken, there might be a chance down in TX, however, with the better upper support. Even there, though, the SRH predicted by the WRF is low.