August in Roswell is the rainiest and the cloudiest month of the year. In August, the weather in Roswell is typically hot. Average daily high temperature in August is about 32 degrees above zero. On average, Roswell has 16 sunny, 9 rainy, and 6 partly cloudy days in August. The rains are usually light. August as well as June and July is considered the most uncomfortable time to visit Roswell.