 Steve Dresner, WTOP Traffic. Now to 7 News First Alert meteorologist Jordan Evans. This afternoon, sun and clouds mixed, a high of 91 degrees, a heat index up to 94, and a south wind at 5 to 10 miles per hour. For tonight, increasing clouds, a low of 75, southeast wind at 5 to 10 miles per hour. For tomorrow, thunderstorm chances throughout the day, high temperature of only 84 degrees, and a southeast wind once again at 5 to 10 miles per hour, and that chance for rain at 80%.