As of 3/16/15 Tucson weather is calling for a 60% probability of showers on Thursday, March 19. So far this year, the forecast has been pretty accurate for the west side of the city, which includes the Casino del Sol Resort. Friday has a slight chance (10%) of showers and Saturday looks to be clear and sunny.
Remember that the 3rd level of the parking garage has been reserved for meet show cars. If you don't have an enclosed trailer, you are welcome to use this facility.