Istanbul Weather in September
In September, Istanbul averages a high of 25°C (78°F) and a low of 16°C (62°F), from 40 years of daily records (1971–2025).
25°C
Average high
78°F
16°C
Average low
62°F
35°C
Record high
95°F · September 17, 1972
9°C
Record low
49°F · September 27, 1997
What September Is Like in Istanbul
- 6 of the 10 warmest Septembers on record in Istanbul have come since 2010.
- The September heat record, 35°C (95°F) on September 17, 1972, has stood for 53 years.
- September 2024 was the 4th warmest September in 40 years of records, 2.9°C (5.2°F) above the long-run average.
- A typical September brings 2.4 days above 30°C (86°F).
At least 1 mm of rain falls on 49% of September days.
Warmest: 2023 (29.3°C)Latest: 2024 (28.2°C)10-year averageLong-run average (25.4°C)
Look Up a Day in September
See the weather in Istanbul on any September date, year by year.
Source: NOAA GHCN-Daily, Istanbul (1971–2007); Istanbul Bolge (Kartal) (2014–2025). Averages cover 1971–2025. How we compute this