July in Wonsan is the cloudiest month of the year. In July, the weather in Wonsan is typically warm. Average daily high temperature in July is about 27 degrees above zero. On average, Wonsan has 16 rainy, 8 partly cloudy, 4 sunny, and 3 cloudy days in July. The rains are usually heavy. July as well as January, February, March, and August is considered the most uncomfortable time to visit Wonsan.