The climate of Calgary is continental, with very cold winters and mild or pleasantly warm summers.
Calgary is the largest city in the province of Alberta and is located at the 51st parallel, 1,100 meters (3,600 feet) above sea level, and east of the Rocky Mountains. In 1988, it hosted the Winter Olympics.
We are in the Canadian prairies, characterized by low precipitation (especially in winter) and strong variations in temperature. On the coldest days of the year, the temperature can drop to -30 °C (-22 °F) or even below. In December 1977, it dropped to -37 °C (-34.5 °F), and in February 1989, to -36 °C (-33 °F). On the hottest days of the year, temperatures can reach 30 °C (86 °F), or even higher. The heat record belongs to August 2018, with 36.5 °C (97.5 °F).
When the chinook blows, the wind that comes down from the mountains, the temperature can reach 10 °C (50 °F), and sometimes 15 °C (59 °F), even in the middle of winter.
The average temperature of the coldest month (January) is of -7.1 °C (19 °F), that of the warmest month (July) is of 16.5 °C (62 °F). Here are the average temperatures.

Precipitation amounts to 425 millimeters (16.7 inches) per year: it is therefore quite scarce. It ranges from 10 mm (0.4 in) in the driest months (January, February, November, December) to 80 mm (3.1 in) in the wettest (June). Summer is the rainiest season due to afternoon thunderstorms, which can be accompanied by hail.
On average, 130 cm (51 in) of snow fall per year. Typically, it can snow from late September to mid-May.
Here is the average precipitation.

On average, there are around 2,395 sunshine hours per year. Calgary is the sunniest city in Canada. Here are the average sunshine hours per day.

Best Time

The best time to visit Calgary is summer, from June to August, since it is the mildest season. However, at night it can be cold, so it may be helpful to bring a jacket and sweater.