When gates at Pimlico open at 8 a.m. for InfieldFest, it will probably be mostly cloudy and mild with temperatures in the upper 60s. Some sun should emerge during the late morning and into the afternoon, as temperatures climb toward 80. Humidity levels will be quite high, so spectators should stay hydrated. Some thunderstorms could develop in the late afternoon or early evening, possibly (40% chance) impacting the race itself. Any storms may produce heavy rain, gusty winds and lightning.