It also could create a traffic nightmare for fans trying to get in the track, which is located 15 miles northeast of Charlotte. Fans going to the Busch race would be required to clear out the grandstands before being allowed back in for the Cup race.
LMS president and general manager H.A. "Humpy" Wheeler said officials would evaluate the weather situation at 8 a.m. Saturday, and if the track is wet, the Busch race would be run at 12:30 p.m. Sunday.
If the track is dry, grandstand gates will open at 8:30 a.m., and the race will run at 11 a.m. Gates for the Winston Cup race will open at 3 p.m. if the Busch race is run.
No decision has been made as to when the races would be run if both are rained out Saturday.
TNT, which was originally scheduled to show the race tape-delayed, will pick up live coverage.
The Winston Cup cars got less than half of one of two scheduled practices in before rain hit the track. Happy Hour was washed out, but the skies cleared early Friday afternoon. Pre-race activities were moved up to allow the race to start as soon as possible, with engines fired and the cars hitting the track.
But the rain resumed. Polesitter Kevin Harvick led the cars to the green and yellow flag, but after nine 55 mph laps, NASCAR displayed the red.
NASCAR spokesman Mike Zizzo said the laps run Friday night will not count, and the full 300 miles will be run as scheduled.