May in Girdwood is the windiest month of the year. In May, the weather in Girdwood is typically cold. Average daily high temperature in May is about 4 degrees above zero. On average, Girdwood has 22 rainy, 5 cloudy, 3 sunny, and 1 snowy day in May. The rains are usually heavy. May as well as June, July, August, and September is considered the most uncomfortable time to visit Girdwood.