May in Courmayeur is the cloudiest month of the year. In May, the weather in Courmayeur is typically warm. Average daily high temperature in May is about 11 degrees above zero. On average, Courmayeur has 19 rainy, 6 partly cloudy, 3 sunny, and 3 cloudy days in May. The rains are usually heavy. May as well as April, June, July, and August is considered the most uncomfortable time to visit Courmayeur.