High pressure will be located off the New England coast to start the weekend, which will produce a southeast wind that will transport some moisture off the Atlantic Ocean and into eastern Pennsylvania. It is possible that there could be some isolated showers and thunderstorms around the track on Saturday, but I think the odds of a dry day are pretty good right now. I only have a 20% chance of rain at the track, so practice and qualifying will most likely stay dry.
A cold front and upper level trough will be crossing the Great Lakes and Ohio Valley on Saturday night, and move into western PA Sunday morning. Showers and thunderstorms are expected along the front, but the question is how far ahead of the front storms may develop. This far out, timing is uncertain, so I will not be specific about when the storms might begin at the track. However, the chances of rain will likely be increasing through the day. The race is scheduled for between 3 pm and 6:15 pm. There is a good chance that rain will arrive before the end of the race, so I'm putting the rain chance at 50% right now. As we get closer to the weekend, the timing should become more clear.
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