Weather in Ottawa in September
In an average September, Ottawa sees a daily high around 21°C and a low around 10°C, based on 1980–2026 of local climate records.
| Average high | 21°C |
|---|---|
| Typical high range | 15°C to 26°C |
| Average low | 10°C |
| Typical low range | 5°C to 16°C |
| Average daily precipitation | 3 mm |
September records
The most extreme September on record for each metric, across 1980–2026. For rainfall, the wettest and driest are by total September accumulation.
High
Highest
34°C
2002-09-09
Lowest
6°C
1992-09-30
Low
Highest
23°C
1983-09-06
Lowest
-2°C
1980-09-29
Feels-like
Highest
48°C
2023-09-05
Lowest
-7°C
1980-09-29
Humidity
Highest
19.8 g/m³
2015-09-07
Lowest
3.6 g/m³
2000-09-28
Wind
Highest
38 km/h
2003-09-19
Lowest
4 km/h
2018-09-12
Gust
Highest
91 km/h
2018-09-21
Lowest
12 km/h
2024-09-13
Precip
Wettest
198 mm
1986
Driest
12 mm
2023
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