December in Cheyenne is the snowiest and the coldest month of the year. In December, the weather in Cheyenne is typically freezing. Average daily high temperature in December is about 1 degree above zero. On average, Cheyenne has 16 partly cloudy, 11 sunny, 2 rainy, 1 snowy, and 1 cloudy day in December. The rains are usually light. December as well as January, February, March, and April is considered the most uncomfortable time to visit Cheyenne.