Weather in Ottawa, Ontario, Canada in September
In an average September, Ottawa sees a daily high around 21°C and a low around 10°C, based on 1981–2026 of local climate records.
| Average high | 21°C |
|---|---|
| Typical high range | 16°C to 26°C |
| Average low | 10°C |
| Typical low range | 5°C to 15°C |
| Average daily precipitation | 3 mm |
September records
The most extreme September on record for each metric, across 1981–2026. For rainfall, the wettest and driest are by total September accumulation.
High
Highest
33°C
2002-09-09
Lowest
6°C
1991-09-30
Low
Highest
20°C
2010-09-02
Lowest
-2°C
1991-09-30
Feels-like
Highest
44°C
2015-09-07
Lowest
-6°C
1981-09-30
Humidity
Highest
19.8 g/m³
2013-09-11
Lowest
3.7 g/m³
2000-09-28
Wind
Highest
25 km/h
2005-09-29
Lowest
5 km/h
1989-09-14
Precip
Wettest
162 mm
2010
Driest
25 mm
2023
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