January in Manhattan is the snowiest and the coldest month of the year. In January, the weather in Manhattan is typically cold. Average daily high temperature in January is about 2 degrees above zero. On average, Manhattan has 14 sunny, 14 partly cloudy, 1 rainy, 1 snowy, and 1 cloudy day in January. The rains are usually moderate. January as well as February and December is considered the most uncomfortable time to visit Manhattan.