In December, the weather in Bol'shaya Kosul' is typically freezing. Average daily high temperature in December is about 12 degrees below zero. On average, Bol'shaya Kosul' has 18 snowy, 12 cloudy, and 1 sunny day in December. The snowfalls are usually light. December as well as January, February, April, and May is considered the most uncomfortable time to visit Bol'shaya Kosul'.