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Hourly Forecast
Daylight Hours
07:08
Sunrise
19:22
Sunset
Moon
Waxing Crescent
11:54
Moonrise
21:02
Moonset
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Weather in Ottawa today, September 15, 2026
Conditions in Ottawa on September 15, 2026 favour clear skies, so the day opens with a fine, sunny outlook. Any interruptions to the blue should be brief rather than lasting. Expect a grey start, with morning cloud around 100% by 07:00. Outdoor plans early on should not rely on bright skies.
Expect highs of 36°C and cooler readings close to 16°C. Moisture in the air spans 38%-86%, with the highest values around 23:00. Airflow remains manageable, reaching about 7.9 km/h around 09:00.
Through the afternoon cloud remains the main feature, with cover near 100% around 12:00. Bright spells should stay limited even as the day wears on. Horizontal visibility sits around 15.8 km, briefly nearer 11.2 km. Daylight runs from 07:08 to 19:22, lasting 12 hours 14 minutes of sunlight today.
Taken together, settled sunshine in Ottawa on September 15, 2026 makes outdoor timing easier, with highs near 36°C.
Frequently asked questions about weather in Ottawa
How warm does it get in Ottawa?
The warmest month in Ottawa is July, with average high temperatures of 32°C. The average temperature during this period is around 27°C.
How cold does it get in Ottawa?
The coldest month in Ottawa is January, with average low temperatures of -4°C. The average temperature during this period is around 0°C.
What is the wettest time of year in Ottawa?
The wettest month in Ottawa is May, with an average of 174mm of precipitation.
What is the driest time of year in Ottawa?
The driest month in Ottawa is February, with an average of 36mm of precipitation.
