January in New Brunswick is the snowiest and the coldest month of the year. In January, the weather in New Brunswick is typically cold. Average daily high temperature in January is about 2 degrees above zero. On average, New Brunswick has 15 partly cloudy, 9 sunny, 5 rainy, 1 snowy, and 1 cloudy day in January. The rains are usually moderate. January as well as February, March, and December is considered the most uncomfortable time to visit New Brunswick.