In May, the weather in Ust-Koksa is typically cold. Average daily high temperature in May is about 9 degrees above zero. On average, Ust-Koksa has 18 rainy, 9 sunny, and 4 partly cloudy days in May. The rains are usually heavy. May as well as January, February, April, and June is considered the most uncomfortable time to visit Ust-Koksa.