Alberta weather in September
September is one of the best months to visit Alberta: highs of 17°C (62°F) and about 53 mm (2.1 in) of rain on average. Nights average 4°C (39°F) and cloud cover 62% (NASA POWER, 2001–2025 averages). It is the 5th wettest month of the year and the 4th warmest. Compared with August, it is cooler and about as wet; October brings highs of 9°C (48°F) and 32 mm (1.3 in) of rain.
Figures are long-term averages for Calgary, the largest city in Alberta. See below for other places.
Is September a good time to visit Alberta?
best month Weather score 69/100.
Yes. September is one of the best months for weather in Alberta.
Does it rain a lot in Alberta in September?
No, it is usually dry: about 53 mm (2.1 in) falls in an average September. It is the 5th wettest month of the year.
How warm is Alberta in September?
Days average 17°C (62°F) and nights 4°C (39°F).
Alberta weather by month
| Month | High | Low | Rain | Cloud | Weather |
|---|---|---|---|---|---|
| January | -3°C (27°F) | -11°C (11°F) | 17 mm | 70% | least pleasant |
| February | -2°C (29°F) | -12°C (10°F) | 21 mm | 69% | least pleasant |
| March | 3°C (37°F) | -8°C (17°F) | 26 mm | 72% | least pleasant |
| April | 9°C (47°F) | -3°C (26°F) | 46 mm | 72% | least pleasant |
| May | 15°C (59°F) | 2°C (36°F) | 73 mm | 70% | fair |
| June | 19°C (66°F) | 7°C (44°F) | 115 mm | 70% | fair |
| July | 24°C (74°F) | 10°C (50°F) | 58 mm | 56% | best |
| August | 22°C (72°F) | 9°C (47°F) | 61 mm | 56% | best |
| September | 17°C (62°F) | 4°C (39°F) | 53 mm | 62% | best |
| October | 9°C (48°F) | -2°C (28°F) | 32 mm | 68% | least pleasant |
| November | 1°C (34°F) | -7°C (19°F) | 23 mm | 71% | least pleasant |
| December | -4°C (26°F) | -12°C (11°F) | 21 mm | 68% | least pleasant |
Sources: 2001–2025 monthly averages from NASA POWER (MERRA-2 reanalysis). Page updated . How we rate months
Weather across Alberta in September
Weather can differ a lot within Alberta: coasts, hills and mountains each have their own climate.
| Place | High | Low | Rain | Weather |
|---|---|---|---|---|
| Calgary | 17°C (62°F) | 4°C (39°F) | 53 mm | best |
| Banff | 11°C (52°F) | 0°C (32°F) | 69 mm | fair |
| Edmonton | 17°C (63°F) | 5°C (41°F) | 41 mm | best |
| Lethbridge | 19°C (67°F) | 6°C (43°F) | 44 mm | best |
| Red Deer | 17°C (63°F) | 5°C (41°F) | 44 mm | best |
| Airdrie | 18°C (64°F) | 5°C (41°F) | 43 mm | best |
| Sherwood Park | 17°C (62°F) | 5°C (41°F) | 39 mm | best |
| Grande Prairie | 16°C (60°F) | 5°C (40°F) | 51 mm | best |
| Fort McMurray | 14°C (58°F) | 4°C (39°F) | 57 mm | fair |
| Medicine Hat | 20°C (69°F) | 7°C (45°F) | 32 mm | best |
| St. Albert | 17°C (63°F) | 5°C (41°F) | 41 mm | best |
| Centre City | 17°C (62°F) | 4°C (39°F) | 53 mm | best |