January weather forecast in Jeju

January in Jeju is the coldest month of the year. In January, the weather in Jeju is typically cold. Average daily high temperature in January is about 6 degrees above zero. On average, Jeju has 11 partly cloudy, 7 rainy, 7 sunny, and 6 cloudy days in January. The rains are usually moderate. January as well as February and December is considered the most uncomfortable time to visit Jeju.