August in Capetown is the coldest month of the year. In August, the weather in Capetown is typically warm. Average daily high temperature in August is about 14 degrees above zero. On average, Capetown has 14 sunny, 11 rainy, and 6 partly cloudy days in August. The rains are usually moderate. August as well as June, July, and September is considered the most uncomfortable time to visit Capetown.