December in Grossostheim is the rainiest, the windiest, and the cloudiest month of the year. In December, the weather in Grossostheim is typically cold. Average daily high temperature in December is about 4 degrees above zero. On average, Grossostheim has 22 rainy, 7 cloudy, and 2 sunny days in December. The rains are usually moderate. December as well as January, February, and November is considered the most uncomfortable time to visit Grossostheim.