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12°
Mostly Clear
Feels Like: 14°
Min: 7°
Max: 15°
The next few hours will be clear, with today reaching 15°C and dropping to 6°C. The coming days will be drizzle
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:55
Sunrise
18:54
Sunset
Moon
Waxing Gibbous
16:56
Moonrise
00:57
Moonset
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View stargazing scoreWeather in Ottawa today, September 21, 2026
Cloud cover dominates in Ottawa on September 21, 2026, keeping sunshine limited. Expect a grey, overcast feel rather than long bright spells. Expect a brighter morning, with limited cloud around 24% by 11:00. Conditions start on a settled note.
The day peaks near 15°C and cools toward 7°C. Moisture in the air spans 48%-75%, with the highest values around 23:00. Winds stay light, near 3.9 km/h by 11:00, so the day feels still more than breezy.
Expect persistent cloud later on, with amounts around 100% by 14:00. Sunshine remains the exception, not the rule. Expect visibility around 16.1 km. Daylight runs from 06:55 to 18:54, lasting 11 hours 58 minutes of sunlight today.
The practical takeaway for Ottawa on September 21, 2026 is a cloudy day that stays usable, just not particularly bright, around 15°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 27°C. The average temperature during this period is around 21°C.
How cold does it get in Ottawa?
The coldest month in Ottawa is January, with average low temperatures of -12°C. The average temperature during this period is around -8°C.
What is the wettest time of year in Ottawa?
The wettest month in Ottawa is April, with an average of 113mm of precipitation.
What is the driest time of year in Ottawa?
The driest month in Ottawa is September, with an average of 69mm of precipitation.
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