Alliston
September
Weather in Alliston for September 2025
Your guide to Alliston weather in September - trends and predictions
In general, the average temperature in Alliston at the beginning of September is 25.1 °C. As the month progressed, temperatures tended to significantly cool down, reaching an average of 20.3 °C by the end of September.
Alliston experiences moderate rainfall in September, with an average of 10 rainy days and a total precipitation of 85.8 mm.
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Temperatures
Rain 🌧️
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20
Dry days
10
Rainy days
0
Snow days
22°/12°
Temperatures
16 km/h
Avg max wind
73 %
Avg humidity
Alliston in September average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  23° | 2  21° | 3 28° | 4 29° | 5 31° | 6  25° | 7  19° |
| 8  19° | 9  21° | 10 22° | 11 24° | 12  24° | 13 22° | 14  23° |
| 15 25° | 16 26° | 17 22° | 18 22° | 19 21° | 20  23° | 21 24° |
| 22 23° | 23 20° | 24 21° | 25 22° | 26 20° | 27 18° | 28 20° |
| 29 21° | 30 20° |
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Temperatures trend during September in Alliston
See the weather trend as well as the moving average line
September weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 Sept. | Partly cloudy | 23° /12° | 0 mm | 6 | |
| 2 Sept. | Light rain shower | 21° /10° | 0.3 mm | 6 | |
| 3 Sept. | Partly cloudy | 28° /13° | 1 mm | 7 | |
| 4 Sept. | Patchy rain possible | 29° /15° | 0.4 mm | 7 | |
| 5 Sept. | Partly cloudy | 31° /16° | 0 mm | 8 | |
| 6 Sept. | Thundery outbreaks possible | 25° /17° | 12.4 mm | 6 | |
| 7 Sept. | Moderate or heavy rain shower | 19° /11° | 12 mm | 5 | |
| 8 Sept. | Overcast | 19° /8° | 0.3 mm | 5 | |
| 9 Sept. | Mist | 21° /9° | 3.2 mm | 5 | |
| 10 Sept. | Overcast | 22° /13° | 0 mm | 6 | |
| 11 Sept. | Light rain shower | 24° /13° | 0.9 mm | 6 | |
| 12 Sept. | Heavy rain | 24° /13° | 15.7 mm | 6 | |
| 13 Sept. | Overcast | 22° /12° | 0 mm | 6 | |
| 14 Sept. | Cloudy | 23° /12° | 0 mm | 6 | |
| 15 Sept. | Mist | 25° /10° | 0 mm | 6 | |
| 16 Sept. | Partly cloudy | 26° /12° | 0 mm | 7 | |
| 17 Sept. | Light rain shower | 22° /12° | 1.6 mm | 5 | |
| 18 Sept. | Mist | 22° /9° | 0 mm | 5 | |
| 19 Sept. | Partly cloudy | 21° /10° | 0 mm | 5 | |
| 20 Sept. | Sunny | 23° /9° | 0 mm | 6 | |
| 21 Sept. | Mist | 24° /14° | 5.6 mm | 5 | |
| 22 Sept. | Mist | 23° /13° | 1 mm | 5 | |
| 23 Sept. | Mist | 20° /12° | 21.3 mm | 5 | |
| 24 Sept. | Mist | 21° /13° | 0 mm | 5 | |
| 25 Sept. | Overcast | 22° /13° | 9.7 mm | 5 | |
| 26 Sept. | Partly cloudy | 20° /12° | 0 mm | 5 | |
| 27 Sept. | Overcast | 18° /11° | 0 mm | 5 | |
| 28 Sept. | Overcast | 20° /11° | 0 mm | 5 | |
| 29 Sept. | Mist | 21° /14° | 0 mm | 5 | |
| 30 Sept. | Mist | 20° /12° | 0 mm | 5 | |
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Important Notice
Our weather forecast for Alliston 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 Alliston forecast closer to your planned date for the most up-to-date weather information.
Alliston in September - FAQ
What are the expected maximum and minimum temperatures in Alliston during September?
Enjoy moderate daytime temperatures of up to 22° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Alliston during September?
Moderate rainfall is anticipated in Alliston during September, with a total of 85.8 mm spread over approximately 10 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Alliston during September?
The average wind speed in Alliston during September is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Alliston
Explore the daily rainfall trends and prepare for Allistons September weather 💧
UV exposure in Alliston during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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