April in Slonim is the sunniest month of the year. In April, the weather in Slonim is typically warm. Average daily high temperature in April is about 12 degrees above zero. On average, Slonim has 10 rainy, 9 sunny, 9 partly cloudy, and 2 cloudy days in April. The rains are usually moderate. April as well as February, March, October, and November is considered the most uncomfortable time to visit Slonim.