LOUISVILLE, Ky. — The severe thunderstorms that soaked Churchill Downs on Friday were expected to clear out well before the Kentucky Derby tomorrow.

"I don't think it will be extreme enough to affect the Derby," meteorologist John Gordon of the National Weather Service in Louisville said.

A line of storms was expected to hit tonight in Louisville, moving east to the Lexington area. Gordon said there would be a threat of tornadoes tonight along Kentucky's southern border. Overnight rain in Louisville should end at about 9 a.m. EDT tomorrow, Gordon said. More rain was possible in the afternoon until about 6 p.m. EDT, just as the race is scheduled to start.

Churchill Downs has a reputation for drying very quickly. If afternoon showers don't develop, the track could be rated fast. Smarty Jones won the last Derby run in the slop in 2004.

"This track handles water as well as any track in the country," Churchill Downs spokesman John Asher said.

Friday's heavy rain cut into Kentucky Oaks Day, second biggest day at Churchill Downs. Elusive Lady was pulled from the $500,000 race after a storm doused the track.

Thousands of fans in exposed seats and bleachers sought cover under the grandstand when the storm struck with full force about 2 p.m.