This is the predicted rainfall totals from May 1 through May 5. It appears that areas of western Tennessee will see up to 7 inches (18cm). Southern Indiana will see up to 6 inches (15cm). A flash flood watch has been issued for areas south of Interstate 70. Rainfall rates of up to 1.25 inches per hour are possible at the height of the storm.
This afternoon, severe weather has been affecting the Mississippi river valley from Minnesota all the way down to Louisiana. At the moment (10:20pm) there are ten tornado warnings in effect across Arkansas, Missouri, and Illinois. Earlier in the evening, there were a dozen simultaneous active warnings. No reports of damage yet though.