Ontario (Toronto)
September
Weather in Ontario for September 2026
Your guide to Ontario weather in September - trends and predictions
Until now, September 2026 in Ontario is slightly cooler than the historical average by 0.9 °C.
The forecast for the next days in Ontario predicts a temperature of 18.1 °C, which is cooler than the historical average.
In general, the average temperature in Ontario at the beginning of September is 25.3 °C. As the month progressed, temperatures tended to significantly cool down, reaching an average of 21.4 °C by the end of September.
Ontario experiences moderate rainfall in September, with an average of 6 rainy days and a total precipitation of 63.4 mm.
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Temperatures
Rain 🌧️
More
24
Dry days
6
Rainy days
0
Snow days
22°/15°
Temperatures
16 km/h
Avg max wind
68 %
Avg humidity
Ontario Weather September
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What’s the Weather Like in Ontario This September?
Discover the average temperatures and weather trends across Ontario’s cities this September.
Temperatures trend during September in Ontario
See the weather trend as well as the moving average line
September weather in Ontario day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 Sept. |  Sunny | 26° /15° | 0.2 mm | 6 | |
| 2 Sept. | Sunny | 25° /15° | 1.2 mm | 5 | |
| 3 Sept. |  Partly cloudy | 27° /16° | 0.1 mm | 6 | |
| 4 Sept. | Partly cloudy | 26° /16° | 3 mm | 6 | |
| 5 Sept. |  Overcast | 26° /16° | 0.7 mm | 7 | |
| 6 Sept. | Partly cloudy | 25° /16° | 6.4 mm | 6 | |
| 7 Sept. | Overcast | 22° /14° | 1.9 mm | 5 | |
| 8 Sept. |  Cloudy | 24° /13° | 1.3 mm | 5 | |
| 9 Sept. | Sunny | 23° /14° | 2.3 mm | 5 | |
| 10 Sept. | Partly cloudy | 24° /14° | 0.1 mm | 6 | |
| 11 Sept. | Overcast | 24° /15° | 0 mm | 6 | |
| 12 Sept. | Partly cloudy | 24° /15° | 0.9 mm | 6 | |
| 13 Sept. |  Patchy rain possible | 23° /14° | 0.2 mm | 5 | |
| 14 Sept. | Patchy rain possible | 24° /14° | 0.2 mm | 6 | |
| 15 Sept. | Sunny | 23° /14° | 0.9 mm | 5 | |
| 16 Sept. | Overcast | 24° /14° | 0 mm | 5 | |
| 17 Sept. | Overcast | 24° /15° | 0.4 mm | 5 | |
| 18 Sept. | Overcast | 24° /15° | 0.8 mm | 5 | |
| 19 Sept. | Sunny | 22° /13° | 0.8 mm | 5 | |
| 20 Sept. | Sunny | 23° /13° | 0.1 mm | 5 | |
| 21 Sept. | Patchy rain possible | 21° /15° | 0.6 mm | 5 | |
| 22 Sept. |  Moderate or heavy rain shower | 21° /12° | 15.8 mm | 5 | |
| 23 Sept. | Moderate rain at times | 19° /12° | 5.2 mm | 5 | |
| 24 Sept. | Sunny | 20° /13° | 1.6 mm | 5 | |
| 25 Sept. | Overcast | 22° /14° | 11.6 mm | 5 | |
| 26 Sept. | Overcast | 21° /13° | 1.8 mm | 4 | |
| 27 Sept. | Overcast | 23° /13° | 0 mm | 4.5 | |
| 28 Sept. | Overcast | 22° /14° | 0.1 mm | 2.7 | |
| 29 Sept. | Overcast | 24° /16° | 0 mm | 2.4 | |
| 30 Sept. | Overcast | 18° /15° | 6.7 mm | 4 | |
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Important Notice
Our weather forecast for Ontario in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Ontario forecast closer to your planned date for the most up-to-date weather information.
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Ontario in September - FAQ
What are the expected maximum and minimum temperatures in Ontario during September?
During September, expect a variety of temperatures with highs around 22° and lows near 15°, suitable for diverse activities and preferences.
How much rainfall should be expected in Ontario during September?
Moderate rainfall is anticipated in Ontario during September, with a total of 63.4 mm spread over approximately 6 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Ontario during September?
The average wind speed in Ontario during September is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Ontario
Explore the daily rainfall trends and prepare for Ontarios September weather 💧
Typically, Ontario has 6 rainy days in September with a total of 63.4 mm of rainfall.
UV exposure in Ontario during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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