December in Karlsruhe is the rainiest and the windiest month of the year. In December, the weather in Karlsruhe is typically cold. Average daily high temperature in December is about 5 degrees above zero. On average, Karlsruhe has 20 rainy, 5 cloudy, 4 sunny, 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 Karlsruhe.