January in Ust'-Donetskiy is the snowiest, the cloudiest, and the most freezing month of the year. In January, the weather in Ust'-Donetskiy is typically freezing. Average daily high temperature in January is about 3 degrees below zero. On average, Ust'-Donetskiy has 18 cloudy, 11 snowy, and 2 sunny days in January. The snowfalls are usually moderate.