After a nice day today rain will return tomorrow. Some severe weather is possible and I'm going to go through all the details below.
There will be two waves of showers & thunderstorms. As it stands no severe weather is expected during wave #1. However, heavy rain can't be ruled out. Wave #2 arriving tomorrow evening is the main concern for severe storm potential.
Thursday - 7am CDT./8am EDT.
Rain showers will begin. Showers should start out light but heavier rain will be possible as the line of showers progresses through Southern Indiana.
Thursday - 11am CDT./12pm EDT.
Showers will become more widespread. A few thunderstorms possible and heavy rain.
Thursday - 5pm CDT./6pm EDT.
By late afternoon wave #1 will move NE creating a brief period of dry-time. If the rain can clear completely and depending on cloud cover the sun may be able peak warming up the atmosphere which then would generate more fuel for wave #2 increasing the severe potential. How this plays out will be a big determining factor of how wave #2 materializes.
Thursday - 6pm CDT./7pm EDT.
The second wave of storms will arrive into far western Southern Indiana.
Thursday - 9pm CDT./10pm EDT.
The main line in wave #2 should begin to clear far western portions in Southern Indiana and continuing to move east.
Thursday - 12am CDT./1am EDT.
As it stands the threat for severe weather looks to clear all of Southern Indiana after midnight central time.
Friday - 5am CDT./6am EDT.
All of Southern Indiana should be mainly dry.
At this point the Storm Prediction Center has all of Southern Indiana under a Slight Risk for severe thunderstorms. This is a level 2 out of 5 so some organized severe weather is possible.
The better risk for severe thunderstorms is to the South. As seen in the graphic below part of Tennessee, Mississippi, Alabama are under a moderate risk for severe thunderstorms. This is a category 4 out of 5 which means there is a potential for a tornado outbreak. Outlining that area is the orange outline which an Enhanced risk category 3 out 5 which means widespread severe weather is possible.
Flash Flooding - While this isn't the main threat some heavy rain is possible and could lead to localized flooding especially in low lying areas. Avoid flooded roadways at all cost. Turn around, Don't drown.
Damaging Winds - This would be the main threat as wind energy will be elevated and could lead to straight line wind damage.
Hail - This would be a low-end threat.
Tornado - The overall threat for tornados is not high but not zero.
Be weather aware tomorrow! Know where you tornado safety spot is just incase a warning was to be issued.