Normal weather for Ontario in September
It's warm in September in Ontario with an average temperature of 23°C. Temperatures this month range from a low of 18°C to a high of 26°C. At night, you can expect temperatures between 12°C and 18°C.
In September, there is an average of 58 mm of precipitation, spread over 8 days. The wind speed is around 4 Bft, mostly coming from the South.
The UV index is a maximum of 7 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Ontario in September |
UK | ||
|---|---|---|---|
 Average Temperature |
23°C | 20°C | |
 High Temp |
26°C | 22°C | |
| Low Temp |
18°C | 17°C | |
 Total Precipitation |
58 mm | 44 mm | |
| Rainy Days |
8 days | 8 days | |
Curious about the climate in other parts of Canada? Check out the weather and climate in places like Vancouver, Toronto, Niagara Falls, or have a look at other destinations in Canada.
Start of September
The month of September starts in Ontario with warm temperatures, averaging around 25°C during the day and nights close to 18°C. A few showers might pop up in the first days of the month, but the weather remains mostly sunny and dry.
Mid-September
By mid-September, the average daytime temperature drops to around 23°C, with nights close to 15°C. Not much precipitation expected during this period. It’s mostly dry with sunshine.
End of September
By the end of September, the average daytime temperature in Ontario will be around 22°C, with nights close to 14°C. A shower might show up, but overall the weather will be dry and sunny.
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Is September a good time to visit Ontario?
Want nice weather? Then September is a great time to be in Ontario. You’ll have pleasant temperatures and not too much rain this month.
Temperature records for Ontario in September
With 34°C, Ontario hit the highest temperature in the last 10 years in September 2016. The lowest daytime temperature in this month was 13°C in 2018. The extreme night temperatures ranged from a low of 6°C to a high of 23°C.
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Daily Temperature in September in Ontario
This chart shows the average daily temperatures, both day and night, for each day in September in Ontario, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in September in Ontario
The chart below shows the average daily precipitation in September for Ontario, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for September, you can expect around 8 days of rain in Ontario.
Daily UV Index in September in Ontario
This chart shows the average daily UV index in September in Ontario, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Ontario Over the Years
This chart shows the average temperature in September in Ontario, measured in degrees Celsius, over the past years.
Total Precipitation in September in Ontario Over the Years
This chart shows the average precipitation in September in Ontario, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in September for Ontario
Click on a specific day in September for detailed info on the typical weather on that day in Ontario. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Ontario
Have you been to Ontario in September?
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Average Weather in Ontario by Month
Click on a month below to see detailed weather info for Ontario. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
