First day of Fall arrives in Toronto with mild weather and changing skies
Posted September 22, 2025 7:09 am.
Last Updated September 22, 2025 7:20 am.
Toronto is stepping into the first day of fall feeling more like mid-July than late September, as warm, humid conditions continue to cap off an unseasonably hot month.
According to Environment Canada, Monday’s forecast calls for a high of 25 °C, feeling closer to 30 °C with the humidex. Skies will be mostly cloudy with a 60 per cent chance of showers and a risk of a thunderstorm late in the afternoon. Overnight, temperatures will dip to 17 °C under partly cloudy skies.
The warm start to autumn follows a September that delivered extended stretches of summer-like weather. Daytime highs frequently reached the mid-20s, with several days climbing above the seasonal norm of 19 °C. Overnight lows also trended warmer than the historical average of 10 °C, keeping conditions mild well into the evenings.
While the city saw occasional rainfall, much of the month was dominated by dry, sunny days — a pattern that extended the feel of summer well past Labour Day.
When Toronto usually feels like fall
Historical climate data from Environment Canada shows that in most years, Toronto’s first stretch of “fall-like” daytime highs — around 20 °C or lower — typically arrives in the final third of September.
- 2024
- Early Sep. (1–10): 24–27 °C
- Mid Sep. (11–20): 21–24 °C
- Late Sep. (21–30): 17–20 °C
- First stretch of highs ≤ 20 °C: Sep. 22–24
- 2023
- Early Sep. 25–28 °C
- Mid Sep. 22–25 °C
- Late Sep. 18–21 °C
- First stretch of highs ≤ 20 °C: Sep. 20–22
- 2022
- Early Sep. 23–26 °C
- Mid Sep. 20–23 °C
- Late Sep. 16–19 °C
- First stretch of highs ≤ 20 °C: Sep. 18–20
- 30-year normal
- Early Sep. ~24 °C
- Mid Sep. ~21 °C
- Late Sep. ~18 °C
- First stretch of highs ≤ 20 °C: Around Sep. 21
Looking ahead, Environment Canada says the warmth will linger for a few more days. Tuesday is expected to bring a mix of sun and cloud with a high near 23 °C, followed by a cooler, sunnier Wednesday with a high of 20 °C.
Temperatures are forecast to settle closer to seasonal norms by late week, with highs around 19–20 °C and overnight lows in the low teens.
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