Sydney Weather in September
In September, Sydney averages a high of 21°C (70°F) and a low of 12°C (54°F), from 55 years of daily records (1971–2026).
21°C
Average high
70°F
12°C
Average low
54°F
34°C
Record high
93°F · September 20, 2023
5°C
Record low
41°F · September 6, 1995
What September Is Like in Sydney
- September 2025 was the 3rd warmest September in 55 years of records, 1.5°C (2.7°F) above the long-run average.
- The coldest September reading, 5°C (41°F) on September 6, 1995, has not been matched in 31 years.
- September in Sydney has become 1.0°C (1.8°F) warmer on average: the 2011–2025 average against 1970–1989.
- The warmest September in the record was 2013; the coldest was 1977.
At least 1 mm of rain falls on 21% of September days, and the month averages 64 mm in total.
Warmest: 2013 (24.0°C)Latest: 2025 (21.8°C)10-year averageLong-run average (20.9°C)
Look Up a Day in September
See the weather in Sydney on any September date, year by year.
Source: NOAA GHCN-Daily, Sydney (Observatory Hill) (1971–2020); Sydney Harbour (Wedding Cake W (2020–2026). Averages cover 1971–2026. How we compute this