July in Bol'shaya Kosul' is the warmest month of the year. In July, the weather in Bol'shaya Kosul' is typically warm. Average daily high temperature in July is about 22 degrees above zero. On average, Bol'shaya Kosul' has 11 partly cloudy, 9 rainy, 7 sunny, and 4 cloudy days in July. The rains are usually light.