May in Vail is the rainiest month of the year. In May, the weather in Vail is typically cold. Average daily high temperature in May is about 7 degrees above zero. On average, Vail has 17 rainy, 7 sunny, 4 partly cloudy, 2 cloudy, and 1 snowy day in May. The rains are usually moderate. May as well as April is considered the most uncomfortable time to visit Vail.