July in Namsos is the warmest month of the year. In July, the weather in Namsos is typically warm. Average daily high temperature in July is about 16 degrees above zero. On average, Namsos has 20 rainy, 5 sunny, 4 partly cloudy, and 2 cloudy days in July. The rains are usually heavy. July as well as March, April, May, and June is considered the most uncomfortable time to visit Namsos.