There is absolutely no way to know if rain is going to affect anything this weekend. Scattered rain chances means exactly what it says. There’s a chance it might rain, there’s a chance it might not rain. If there is rain, how much and the timing is really all that matters. There were a couple days last week where it rained 20 miles away from me, and I didn’t see a drop on any of those days. You can’t predict where it MIGHT rain. I went to an IndyCar/USAC double at Richmond, VA one year. There was a 90% chance of rain on race day. It was literally raining 10 miles from the track in every direction. Didn’t see a drop of rain all night, it was like we were in a rain free vortex. The only place it matters is the plot of land Kokomo Speedway sits on, no way to know if that gets rain.

If I based my racing on forecasts, I’d see pretty much 0 races every year.

If you’re looking for what local Indy weather said, Thursday has the highest chance of rain. Friday and Saturday better. Saturday looks to be the driest.