January in Calais is the cloudiest month of the year. In January, the weather in Calais is typically cold. Average daily high temperature in January is about 7 degrees above zero. On average, Calais has 20 rainy, 5 cloudy, 4 sunny, and 2 partly cloudy days in January. The rains are usually moderate. January as well as February, March, October, and November is considered the most uncomfortable time to visit Calais.