January in Hyesan is the sunniest and the most freezing month of the year. In January, the weather in Hyesan is typically freezing. Average daily high temperature in January is about 9 degrees below zero. On average, Hyesan has 15 sunny, 7 partly cloudy, 5 snowy, and 4 cloudy days in January. The snowfalls are usually light. January as well as March, April, May, and June is considered the most uncomfortable time to visit Hyesan.