May in Bergen is the sunniest month of the year. In May, the weather in Bergen is typically warm. Average daily high temperature in May is about 11 degrees above zero. On average, Bergen has 15 rainy, 9 sunny, 5 partly cloudy, and 2 cloudy days in May. The rains are usually heavy. May as well as January, February, March, and April is considered the most uncomfortable time to visit Bergen.