Sea temperature in Ios in September
The sea around Ios averages 25°C in September, usually between 24°C and 26°C. That is warm enough for most people to swim comfortably.
Average25°CWarm
Usual range24°C–26°C80% of readings
vs August−1.0°cooler
vs October−1.9°cooler next month
Through the year
Monthly averages 2023–2025. Water at 22°C or warmer: June–October.
September in recent years
| 2023 | 25°C |
|---|---|
| 2024 | 25°C |
| 2025 | 24°C |
Nearby in September
Beaches in Ios
10 of 10 beaches have an Excellent EU water-quality grade. See which ones are calm today.