Weather in Calgary in September 2025
Average weather
Average temperature in Calgary in September
Going from a maximum of +84°F during the day to a minimum of +36°F during the night, the temperature in September averages around +70°F.
The average maximum temperature goes down 52% by the end of the month, compared with the beginning of the month, from +77°F to +52°F.
Is Calgary warm or cold in September?
Calgary is typically mild in September.
Maximum temperatures go down compared to the previous month from +75°F to +66°F. The minimum temperature also goes down from +50°F to +41°F.
Pack a light jacket as it will be warm in the day and cool in the evenings.
Take a look at how September is compared to other months in Calgary:
Climate in Calgary in September
| August | September | October | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +75°F | +66°F | +54°F | ||||
| Min. temperature | ||||||
| +27°F | +16°F | -15°F | ||||
| Max. temperature | ||||||
| +99°F | +93°F | +81°F | ||||
| Rainfall | ||||||
| 67 mm | 44 mm | 16 mm | ||||
| Wind | ||||||
| 3 m/s | 3 m/s | 3 m/s | ||||
| Humidity | ||||||
| 61% | 60% | 60% | ||||
| Air pressure | ||||||
| 1014 HPa | 1014 HPa | 1012 HPa | ||||
| Sunny days | ||||||
| 4 | 5 | 4 | ||||
| Cloudy days | ||||||
| 9 | 12 | 17 | ||||
| Rainy days | ||||||
| 12 | 10 | 6 | ||||
| Snowy days | ||||||
| 0 | 1 | 5 | ||||
September weather is still as good as in August. It’s getting colder in September. From +75°F in the day, the average maximum temperature lowers to +66°F. As September arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 67 mm to 44 mm. It feels drier, as humidity decreases from 61% to 60%. The average wind speed doesn’t change much during September, staying around 3 m/s. The good news is there are likely to be more sunny days in September, from 4 to 5.
October brings much the same weather, it remains good.
Wind
The average wind speed is 3 m/s getting up to 5 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in Calgary is gradually increasing during September, going from 2 m/s to 5 m/s over the course of the month.
Rain
Snow
Here’s how September is compared with other months in the amount of snow, total mm:
How was the weather last September in Calgary?
Climate Change Over the Years
The climate in Calgary in September has not changed that much over the last 43 years.
The average temperature was the lowest in 1996 (+47°F) and the highest in 2023 (+56°F). The driest year was 1979 with only 203 mm of rainfall, and the wettest year was 2019 with 702 mm.
FAQ
Is September a good time to visit Calgary?
Can you sunbathe in Calgary in September?
Is Calgary rainy in September?
Is it sunny in Calgary in September?
Other cities in Canada
Monthly weather in Calgary
Source of the data
For this page, we’ve looked at the typical weather in Calgary, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.