I'd assume they have the track sealed-off right now in anticipation of the rain. We've seen this movie before with the 4 Crown race....rain on Friday, clears-up Saturday morning and we run the USAC portion Sat night. Just checked that Nat Weathr Serv site for Greenville - shows rain over by early morning Sat with the wind shifting to the NW in the morning which means the front has come through.
Let's think positive, and we'll see a great race tomorrow! I'm so exicted, I won't be able to sleep tonight! My favorite race day of the year!!