July in Mankato is the sunniest and the warmest month of the year. In July, the weather in Mankato is typically warm. Average daily high temperature in July is about 27 degrees above zero. On average, Mankato has 23 sunny, 6 partly cloudy, and 2 rainy days in July. The rains are usually light. July as well as August and September is considered the most comfortable time to visit Mankato.