Calgary has a monsoon-influenced humid continental climate (Koppen: Dwb, Trewartha: Dclo bordering Dcbo), with warm, wet summers and cold, dry, but highly variable winters. The city has an average temperature range from in July to in January. Average temperatures at Springbank Airport (slightly west of Calgary) range from in July to in January. The record high temperature is , recorded on August 10, 2018, and the record low temperature is , held on February 4, 1893. However, in recent years, due to climate change, yearly low temperatures usually hover between and .Winters are cold, and the air temperature drops to or below for 22 days of the year on average, and as low as for 3.7 days of the year on average. These temperatures are frequently interrupted by warm, dry chinook winds that blow into Alberta over the mountains. These winds can raise the winter temperature by and as much as in just a few hours, which may last several days. Calgary's proximity to the Rocky Mountains also affects winter temperatures resulting in a mixture of lows and highs, and tends to result in a mild winter for a city in the Prairie Provinces. Temperatures are also affected by the wind chill factor; Calgary's average wind speed is , one of the highest among Canadian cities. In the summer, daytime temperatures range from and exceed for an average of 5.1 days in June, July, and August, and occasionally as late as September or as early as May. As a consequence of Calgary's high elevation and aridity, summer days are often not humid, unlike many other major cities in Canada. Summer evenings also tend to cool off, with monthly average low temperatures reaching throughout the summer months. The summer of 1977 saw no dew point above . Summer 1911 saw no daily minimum temperature above . The summer of 1995 in Calgary saw a maximum yearly temperature of , the most recent instance of Calgary recording an entire year where summer does not see temperatures exceeding .

The wettest month is June with an average precipitation of , while the driest month is January with an average precipitation of . Calgary International Airport in the northeastern section of the city receives an average of of precipitation annually, with of that occurring in the form of rain, and as snow. The most rainfall occurs in June and the most snowfall in March. Calgary has also recorded snow every month of the year. It last snowed in July on July 15, 1999."Hourly Data Report for July 15, 1999". climate.weather.gc.ca. Government of Canada. October 31, 2011. Archived from the original on August 10, 2018. Retrieved February 15. 2025. 06:00 Rain, Snow, Fog The relatively low amount of precipitation in Calgary, when compared to other cities like Toronto, Vancouver, and Montreal, also gives Calgary a climate close to a cool semi-arid climate (Koppen: BSk, Trewartha: BSlo bordering Bsbo).

Thunderstorms can be frequent and sometimes severe, with most of them occurring in the summer months. Calgary lies within Alberta's Hailstorm Alley and is prone to damaging hailstorms every few years. A hailstorm that struck Calgary on September 7, 1991, was one of the most destructive natural disasters in Canadian history, with over $400 million in damage. Further hailstorms struck the city, one on June 13, 2020, causing $1.3 billion in damages. Another occurred on August 5, 2024, became the second-costliest event in Canadian history, as of May 2025, causing $3.25 billion in damage. Being west of the dry line on most occasions, tornadoes are rare in the region.

Calgary has the sunniest days year-round of Canada's 100 largest cities, with slightly over 332 days of sun; it has on average 2,396 hours of sunshine annually, with an average relative humidity of 55% in the winter and 45% in the summer (15:00 MST).

Calgary falls into the NRC Plant Hardiness Zone 4a and USDA zone 4b, as unlike NRC zones, USDA zones are solely based on low temperature. The average low temperature for Calgary is , which would fall under USDA zone 4b.

Calgary has a short growing season, lasting 115 days between May 23 and September 15 on average.

On November 15, 2021, Calgary City Council voted to declare a climate emergency. A climate emergency declaration is a resolution passed by a governing body such as a city council. It puts the local government on record in support of emergency action to respond to climate change and recognizes the pace and scale of action needed. On May 27, 2026, Council voted to rescind its emergency declaration.

Data

Calgary International Airport maximum records: Record high temperature of recorded on August 10, 2018 Record high daily minimum of recorded on July 24, 2024 Record high dew point of recorded on July 2, 2013 Most humid month with an average monthly dew point of recorded during July 2007 Warmest month with an average monthly mean temperature of recorded during July 2024 Warmest monthly average daily minimum of recorded during July 2024 Warmest monthly average daily maximum of recorded during July 1936 July 1936 saw no daily maximum temperature below July 2021 saw no temperature below August 2004 saw no dew point below

The average yearly maximum daily minimum temperature is and the average yearly maximum dew point is at Calgary International Airport.

Notes

References