Saturday is going to turn out to be another great day at the track, as skies will be partly to mostly cloudy throughout the day. The afternoon high will be around 79 degrees. Winds will be out of the north-northwest at 2-5 MPH. For the night time hours, there is a slight risk for severe storms in the Indianapolis area, mainly for another line of storms that is expected to move through during the overnight hours around or just after 1AM. The main threats will be from damaging winds and large hail, and there is a possibility for a few tornadoes as well. The latest NAM-3k model run is keeping the storms just south of Indianapolis, but not far enough to be comfortable to say there is no risk. Once again, stay weather aware, especially if you're camping out.
I may have some good news for Sunday for the Indianapolis 500. The latest run of the NAM-3k is keeping the main bulk of the rain and storm activity well to the south of Indianapolis. There will be another wave of storms that will be approaching the area, but it looks like it won't reach the area until well after the race is over. Now I am not ruling out a scattered shower or a brief thunderstorm to move over the track during the day, but as of now, it doesn't look all that bad. So my official forecast would be: Storms ending before 8AM, then skies will be mostly cloudy throughout the day. A passing shower or thunderstorm is possible during the day, but the likelihood of that is small at this point. The afternoon high is expected to be around 77 degrees, and the winds will be out of the south at 5-8 MPH. Chance of rain from 10AM-4PM will be around 20%.
Radar is up and running on the site, so feel free to use it at anytime. It refreshes every 60 seconds, so it will update the latest radar image in from the NWS Indianapolis as soon as it is uploaded. I'll have more updates throughout the weekend, especially on Sunday if rain develops around the track area.