A low pressure system will track across the Ohio River Valley on Wednesday night and Thursday morning, which will bring a chance of light rain showers. I don't expect this to have much impact as most of it should be gone before any on track activities take place on Thursday. The rest of the day will be mostly sunny and cool, great for Indy Lights qualifying.
Coors Light Carb Day looks absolutely perfect. There will be plenty of sunshine all day, with comfortable temperatures reaching the lower 70s, light winds, and low humidity. You couldn't ask for better weather for the Indy Lights Freedom 100.
Legends Day looks great too, with temperatures getting a little warmer, but still quite comfortable. Highs will be in the mid 70s under mostly sunny skies. It will be great weather for taking in the Pro Mazda and USF2000 series at Lucas Oil Raceway in the afternoon.
Unfortunately, the greatest threat of rain through the entire event will be on race day. The high pressure system that will provide beautiful weather Friday and Saturday will be tracking east, while a low pressure system develops over the Plains and tracks east. The southerly flow between these systems will be transporting more moisture into Indiana by Sunday, resulting in more clouds and higher humidity. While it looks like there could be a chance of rain any time of the day, it does appear that the chance of rain will be increasing through the day as the low pressure system gets closer. There is good model agreement with this pattern, so my confidence in this forecast is medium to high. I'm going to start the forecast with a 50% chance of rain this far out, but if the models maintain some consistency over the next few days, I expect that the rain chance will be rising with later forecast updates. Stay tuned.