September in Lensk is the rainiest month of the year. In September, the weather in Lensk is typically cold. Average daily high temperature in September is about 7 degrees above zero. On average, Lensk has 23 rainy, 4 cloudy, and 3 sunny days in September. The rains are usually moderate. September as well as January, February, March, and April is considered the most uncomfortable time to visit Lensk.