December in Folkestone is the windiest month of the year. In December, the weather in Folkestone is typically cold. Average daily high temperature in December is about 8 degrees above zero. On average, Folkestone has 18 rainy, 5 cloudy, 4 sunny, and 4 partly cloudy days in December. The rains are usually moderate. December as well as January, February, October, and November is considered the most uncomfortable time to visit Folkestone.