January in Hanover is the snowiest and the coldest month of the year. In January, the weather in Hanover is typically cold. Average daily high temperature in January is about 1 degree above zero. On average, Hanover has 15 partly cloudy, 7 sunny, 4 rainy, 4 cloudy, and 1 snowy day in January. The rains are usually moderate. January as well as February, March, May, and December is considered the most uncomfortable time to visit Hanover.