It is likely going to be pretty rough for areas of Missouri. Arkansas. Kentucky. Illinois, and TN this afternoon and tonight
Right now, I say that Central and Eastern Arkansas and Southern, Central Missouri, Southern Illinois will be the worst. West Kentucky and West TN will likely be impacted between 7 pm and midnight.
Likely scenario is that supercells will develop over Central Arkansas, Missouri and they will form into a squall line as they move east. The line should be formed prior to reaching the Mississippi River. Any supercells that form ahead of the line will likely contain strong tornadoes.
Right now, the atmosphere is ripe for an outbreak, with plenty of moisture and instability to support large supercells.
If the sun stays out for a long period of time, I would say that we could see some very bad weather. Hopefully cloud cover will build and keep the threat lower