In December, the weather in Ust'-Kulom is typically freezing. Average daily high temperature in December is about 10 degrees below zero. On average, Ust'-Kulom has 17 snowy, 13 cloudy, and 1 sunny day in December. The snowfalls are usually light. December as well as January, February, April, and September is considered the most uncomfortable time to visit Ust'-Kulom.