August in Nonsan is the warmest month of the year. In August, the weather in Nonsan is typically hot. Average daily high temperature in August is about 28 degrees above zero. On average, Nonsan has 18 rainy, 11 sunny, and 2 partly cloudy days in August. The rains are usually heavy. August as well as January, February, July, and December is considered the most uncomfortable time to visit Nonsan.