December in South Lake Tahoe is the snowiest and the coldest month of the year. In December, the weather in South Lake Tahoe is typically cold. Average daily high temperature in December is about 2 degrees above zero. On average, South Lake Tahoe has 10 rainy, 9 sunny, 7 partly cloudy, 3 cloudy, and 2 snowy days in December. The rains are usually heavy. December as well as January, February, March, and April is considered the most uncomfortable time to visit South Lake Tahoe.