April in Calgary is the windiest and the cloudiest month of the year. In April, the weather in Calgary is typically warm. Average daily high temperature in April is about 10 degrees above zero. On average, Calgary has 9 cloudy, 9 partly cloudy, 6 sunny, 4 rainy, and 2 snowy days in April. The rains are usually moderate. April as well as February, March, May, and June is considered the most uncomfortable time to visit Calgary.