January in Washington is the snowiest and the coldest month of the year. In January, the weather in Washington is typically cold. Average daily high temperature in January is about 4 degrees above zero. On average, Washington has 16 partly cloudy, 10 sunny, 4 rainy, and 1 snowy day in January. The rains are usually moderate. January as well as February, March, and December is considered the most uncomfortable time to visit Washington.