In April, the weather in Mäntsälä is typically cold. Average daily high temperature in April is about 7 degrees above zero. On average, Mäntsälä has 12 rainy, 8 cloudy, 5 sunny, and 5 partly cloudy days in April. The rains are usually moderate. April as well as March, October, and November is considered the most uncomfortable time to visit Mäntsälä.