December in Namsos is the windiest month of the year. In December, the weather in Namsos is typically freezing. Average daily high temperature in December is about zero. On average, Namsos has 16 snowy, 9 rainy, 4 sunny, and 2 partly cloudy days in December. The snowfalls are usually heavy. December as well as March, April, May, and June is considered the most uncomfortable time to visit Namsos.