August in Guiyang is the sunniest month of the year. In August, the weather in Guiyang is typically warm. Average daily high temperature in August is about 27 degrees above zero. On average, Guiyang has 18 rainy, 6 sunny, 4 partly cloudy, and 3 cloudy days in August. The rains are usually heavy. August as well as January, February, March, and April is considered the most uncomfortable time to visit Guiyang.