As you handicap this year’s Kentucky Derby, you better ask yourself not only who can get a mile and a quarter, but who can do so on an off track. Some of this year’s contenders have been running on synthetic surfaces and never touched a track listed as sloppy or muddy. That might change May 2 because Churchill Downs has a traditional dirt surface, and the forecast is for rain.

It is expected to rain in Louisville, Ky., on April 30, and the forecast is no better for the weekend. The National Weather Service is predicting a 60% chance of precipitation May 1 (Kentucky Oaks day), and a 60% chance again May 2 (Kentucky Derby day).

There is a 70% chance of showers from 1-7 p.m. April 30 and another strong chance the morning of May 1. The forecast for May 1 also calls for winds of 10-15 m.p.h.

For Kentucky Derby day, the forecast is for thunderstorms with a high temperature in the upper 60s