May in Ostromichi is the rainiest month of the year. In May, the weather in Ostromichi is typically warm. Average daily high temperature in May is about 18 degrees above zero. On average, Ostromichi has 19 rainy, 9 sunny, and 3 partly cloudy days in May. The rains are usually moderate. May as well as February, March, November, and December is considered the most uncomfortable time to visit Ostromichi.