May in Klosters-Serneus is the rainiest month of the year. In May, the weather in Klosters-Serneus is typically cold. Average daily high temperature in May is about 9 degrees above zero. On average, Klosters-Serneus has 22 rainy, 6 sunny, and 3 partly cloudy days in May. The rains are usually heavy. May as well as March, April, June, and July is considered the most uncomfortable time to visit Klosters-Serneus.