August in Destin is the rainiest and the hottest month of the year. In August, the weather in Destin is typically hot. Average daily high temperature in August is about 29 degrees above zero. On average, Destin has 16 rainy, 11 sunny, 3 partly cloudy, and 1 cloudy day in August. The rains are usually heavy. August as well as July is considered the most uncomfortable time to visit Destin.