In September, the weather in Ostrovskoe is typically warm. Average daily high temperature in September is about 13 degrees above zero. On average, Ostrovskoe has 15 rainy, 11 cloudy, 3 sunny, and 1 partly cloudy day in September. The rains are usually moderate. September as well as January, April, October, and November is considered the most uncomfortable time to visit Ostrovskoe.