February in Ust-Ilimsk is the cloudiest month of the year. In February, the weather in Ust-Ilimsk is typically freezing. Average daily high temperature in February is about 16 degrees below zero. On average, Ust-Ilimsk has 21 cloudy, 7 snowy, and 1 sunny day in February. The snowfalls are usually light. February as well as January, April, May, and September is considered the most uncomfortable time to visit Ust-Ilimsk.