See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
18°
Mostly Cloudy
Feels Like: 20°
Min: 17°
Max: 29°
The next few hours will be overcast, with today reaching 29°C and dropping to 16°C. The coming days will be clear throughout the day.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:39
Sunrise
18:51
Sunset
Moon
Waxing Crescent
11:15
Moonrise
20:44
Moonset
Daily Forecast
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Wednesday
Thursday
Friday
Saturday
Sunday
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Thursday
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Weather in Ontario today, September 15, 2026
Ontario starts September 15, 2026 under largely sunny skies, with bright spells setting the tone from the outset. Outdoor plans should enjoy long stretches of open sky as the day unfolds. Expect a grey start, with morning cloud around 100% by 05:00. Outdoor plans early on should not rely on bright skies.
Temperatures climb from an overnight low near 17°C toward a daytime high of about 29°C. The air stays humid, with relative humidity between 40% and 91% and the peak around 04:00. A lighter breeze peaks around 16:00 near 5.5 km/h.
Expect a more open afternoon, with limited cloud around 21% by 21:00. Residual damp risk should be lower than earlier. Visibility holds near 15.3 km, though it can fall to 13.2 km. Expect sunrise at 06:39, sunset at 18:51, and 12 hours 12 minutes of sunlight today overall.
In short, September 15, 2026 looks like a fine day in Ontario for being outside, peaking around 29°C.
Frequently asked questions about weather in Ontario
How warm does it get in Ontario?
The warmest month in Ontario is August, with average high temperatures of 31°C. The average temperature during this period is around 25°C.
How cold does it get in Ontario?
The coldest month in Ontario is January, with average low temperatures of 7°C. The average temperature during this period is around 12°C.
What is the wettest time of year in Ontario?
The wettest month in Ontario is January, with an average of 94mm of precipitation.
What is the driest time of year in Ontario?
The driest month in Ontario is July, with an average of 1mm of precipitation.
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