January in Mamaroneck is the coldest month of the year. In January, the weather in Mamaroneck is typically cold. Average daily high temperature in January is about 1 degree above zero. On average, Mamaroneck has 14 partly cloudy, 8 sunny, 5 rainy, 3 cloudy, 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 Mamaroneck.