October in Kostroma is the rainiest month of the year. In October, the weather in Kostroma is typically cold. Average daily high temperature in October is about 5 degrees above zero. On average, Kostroma has 15 rainy, 14 cloudy, and 2 sunny days in October. The rains are usually moderate. October as well as January, April, and November is considered the most uncomfortable time to visit Kostroma.