In September, the weather in Omutninsk is typically warm. Average daily high temperature in September is about 12 degrees above zero. On average, Omutninsk has 14 cloudy, 13 rainy, 2 sunny, and 1 partly cloudy day in September. The rains are usually moderate. September as well as January, February, April, and October is considered the most uncomfortable time to visit Omutninsk.