Toronto Weather in September

In September, Toronto averages a high of 21°C (71°F) and a low of 14°C (57°F), from 54 years of daily records (1971–2025).

21°C

Average high

71°F

14°C

Average low

57°F

34°C

Record high

93°F · September 10, 1983

2°C

Record low

36°F · September 30, 1993

What September Is Like in Toronto

September 2024 was the 2nd warmest September in 54 years of records, 2.7°C (4.8°F) above the long-run average.
6 of the 10 warmest Septembers on record in Toronto have come since 2010.
September in Toronto has become 1.5°C (2.8°F) warmer on average: the 2010–2024 average against 1970–1989.
The September heat record, 34°C (93°F) on September 10, 1983, has stood for 42 years.

At least 1 mm of rain falls on 26% of September days, and the month averages 75 mm in total.

Average daytime high in Toronto, every September since 1971

Warmest: 2002 (25.6°C)Latest: 2024 (24.7°C)10-year averageLong-run average (21.5°C)

See the weather in Toronto on any September date, year by year.

Source: NOAA GHCN-Daily, Toronto (1971–2003); Toronto City (2002–2025). Averages cover 1971–2025. How we compute this