In December, the weather in Tumnin is typically freezing. Average daily high temperature in December is about 13 degrees below zero. On average, Tumnin has 11 sunny, 9 partly cloudy, 7 snowy, and 4 cloudy days in December. The snowfalls are usually moderate. December as well as January, February, April, and May is considered the most uncomfortable time to visit Tumnin.