August in Calgary is the warmest month of the year. In August, the weather in Calgary is typically warm. Average daily high temperature in August is about 22 degrees above zero. On average, Calgary has 15 sunny, 12 partly cloudy, and 4 rainy days in August. The rains are usually light. August as well as {{month_nom: February}}, and {{month_nom: February}} is considered the most comfortable time to visit Calgary.