January in Nikko is the coldest month of the year. In January, the weather in Nikko is typically cold. Average daily high temperature in January is about 2 degrees above zero. On average, Nikko has 11 partly cloudy, 10 rainy, 8 sunny, and 2 cloudy days in January. The rains are usually light. January as well as February, March, April, and May is considered the most uncomfortable time to visit Nikko.