Saturday is the 30th year for the Thunder Over Louisville, which kicks off the Derby Festival. Nothing can rain on that parade. Well except perhaps maybe rain itself. But no worries, right now the weather forecast shows the day will start off dry and chilly, about 40 degrees. There is a small chance of showers early in the day before 2 p.m., but daytime will otherwise be dry, with temperatures reaching the high-60s, according to the National Weather Service.