Conditions on Thursday are becoming more favorable during the evening/overnight hours for severe storms capable of damaging gusts, large hail, and a tornado or two appear possible, though this risk is a bit more uncertain/conditional, and coverage may be low.

 

 

Today, an associated jet streak will translate eastward into the Ozarks, causing a negatively tilted mid-level trough to flow northeastward into the Upper Midwest. High-wind secondary jet streams will enter the mid-Mississippi Valley from the northeast. There will be widespread severe weather today as a result of a strong, large-scale lift that will stretch a vast, moist sector from the Great Lakes into the Ohio Valley.

A low will form near the surface and pass the eastern Dakotas in a northerly direction. While a cold front advances eastward into the mid- to upper Mississippi Valley, a well-defined warm front will travel northward into Wisconsin. Much of the moist sector will experience mild instability ahead of the front due to surface dewpoints ranging from the mid-60s to the lower 70s F. In the afternoon, storms are predicted to develop south-southeastward along and ahead of the front, with the earliest thunderstorms predicted to form close to the mid-level low over the upper Mississippi Valley.

There will be rather less widespread storm coverage in the lower Ohio Valley. Nonetheless, any cells that are able to form inside the extremely unstable air mass will probably grow into supercells that produce huge hail and powerful gusts. Additionally, there is a risk of tornadoes. The distribution and intensity of instability may determine the development of a corridor of increased severe hazard, which is expected to occur somewhere around the Ohio River in the late afternoon.

 

 

 

 

 

The following HRRR modeling simulations are from 5 pm to 12 am EDT.

 

 

 

Update:

Storms may develop late afternoon to our west, moving into the NWS-Louisville coverage area in the evening (9 pm-2 am EDT). If storms develop, severe storms will be possible. There is a significant possibility that storms are unable to develop. The main threats will be large hail, locally damaging winds, heavy rain, and a tornado can't be ruled out. If these storms are weak or there are no storms tonight, that would increase the confidence in Friday's severe weather. 

1 hour ago, nWo said:

Update:

Storms may develop late afternoon to our west, moving into the NWS-Louisville coverage area in the evening (9 pm-2 am EDT). If storms develop, severe storms will be possible. There is a significant possibility that storms are unable to develop. The main threats will be large hail, locally damaging winds, heavy rain, and a tornado can't be ruled out. If these storms are weak or there are no storms tonight, that would increase the confidence in Friday's severe weather. 

Seems like most guidance is on the same page about today in thinking that storms likely won't be able to break the cap, setting us up for real problems tomorrow. 

2 hours ago, TheDeuce said:

Seems like most guidance is on the same page about today in thinking that storms likely won't be able to break the cap, setting us up for real problems tomorrow. 

That is what is concerning to me.