January weather forecast in Watertown

January in Watertown is the snowiest and the most freezing month of the year. In January, the weather in Watertown is typically freezing. Average daily high temperature in January is about 5 degrees below zero. On average, Watertown has 10 partly cloudy, 9 sunny, 7 cloudy, and 5 snowy days in January. The snowfalls are usually light.