Sea temperature in Ios in December
The sea around Ios averages 19°C in December, usually between 18°C and 20°C. That is cool: fine for a quick swim, many people find it chilly.
Average19°CCool
Usual range18°C–20°C80% of readings
vs November−2.0°cooler
vs January−1.5°cooler next month
Through the year
Monthly averages 2023–2025. Water at 22°C or warmer: June–October.
December in recent years
| 2023 | 19°C |
|---|---|
| 2024 | 19°C |
| 2025 | 20°C |
Nearby in December
Beaches in Ios
10 of 10 beaches have an Excellent EU water-quality grade. See which ones are calm today.