In May, the weather in Ust-Kamchatsk is typically cold. Average daily high temperature in May is about 4 degrees above zero. On average, Ust-Kamchatsk has 11 cloudy, 10 partly cloudy, 5 rainy, and 5 sunny days in May. The rains are usually moderate. May as well as June, August, September, and October is considered the most uncomfortable time to visit Ust-Kamchatsk.