In December, the weather in Fredericton is typically freezing. Average daily high temperature in December is about 1 degree below zero. On average, Fredericton has 9 partly cloudy, 8 sunny, 6 cloudy, 5 snowy, and 3 rainy days in December. The snowfalls are usually heavy. December as well as March, April, May, and October is considered the most uncomfortable time to visit Fredericton.