Supposedly they're putting a tarp on the Pro-Ride Friday night:
With a forecast for rain and five days of racing having been lost this meet because of drainage problems with the Santa Anita Pro-Ride main track, track officials are taking precautions. Late Friday, a plastic tarp is scheduled to be placed over the main track.
"If it happens, it will be the first time in history a racetrack will be covered," said the track's superintendent, Richard Tedesco.
http://www.drf.com/news/article/111210.html
NT