December in Cologne is the rainiest and the windiest month of the year. In December, the weather in Cologne is typically cold. Average daily high temperature in December is about 6 degrees above zero. On average, Cologne has 24 rainy, 3 sunny, 2 cloudy, and 2 partly cloudy days in December. The rains are usually moderate. December as well as January, February, and November is considered the most uncomfortable time to visit Cologne.