Here was Jim Cantore an hour ago on Twitter:
I will start today like I did Sunday. There are MANY opportunities for rain today at the #Daytona500: Drying by sunset.
Here is the current radar. Everything seems to be moving directly west-to-east. The speedway is located roughly under the center of the letter "n" in "Daytona".
There seems to be a dry-ish patch over Ocala right now. That will take about 2 hours to reach the speedway. Track drying could begin then. After that point, we just have to hope that the batch in the Gulf just north of Homosassa Springs (that's a city, not a slur) tracks slightly to the north. If so, we could get a little lucky and get this in tonight.