2-15-18 Illinois PM Update on heavy rain and isolated strong storm threat in southern Illinois this evening. N.

Video (5 min):

The Storm Prediction Center added a marginal risk for a few gusty storms capable of gusty winds and perhaps a brief spin-up.  This was added due to enough instability building with peeks of sun and wind energy in play.  

Forecast radar from 3pm today to 11am Friday is shown below.  I think storms will develop after 6pm, with 7pm to 2am CT being our main time-frame to watch for locally strong storms, tending to weaken after midnight.  Beyond that, it will be more of a heavy rain concern for far southern portions of the state into the pre-dawn of Friday.  

 

Here is the latest rainfall guidance through tomorrow morning.  Notice some differences in the data regarding amounts, but similar in placement of a heavier band near Salem to Olney where 1-2″+ is very possible.  Watch for a local flash flood threat here.  Note rain totals are drastically less north, where many spots only see a few hundredths as you will not see any storms.