December in Sayansk is the snowiest month of the year. In December, the weather in Sayansk is typically freezing. Average daily high temperature in December is about 14 degrees below zero. On average, Sayansk has 10 cloudy, 8 partly cloudy, 7 snowy, and 6 sunny days in December. The snowfalls are usually light. December as well as January and February is considered the most uncomfortable time to visit Sayansk.