The heat and humidity will continue to build over the next three days. We can expect the air temperature to reach the low 90s through Friday afternoon. After today heat indices will exceed 100 by 3 p.m. Thursday and Friday will be the hottest and most humid.
We are also looking at daily rain chances through Friday night. Today will bring the lowest rain chances, on the order of 20%, only southwest of Indy. Those rain chances do go up on Thursday and Friday as a result of an approaching cold front. We'll see a 30-40% chance for showers and storms on Thursday and Friday afternoons. Some storms could be strong.
That cold front will clear central Indiana by Saturday AM. It will also knock some of this oppressive heat and humidity out of the air, so the weekend will be MUCH more comfortable with highs in the mid 80s, lower humidity and sunny skies.