Sea temperature in Kos in May
The sea around Kos averages 20°C in May, usually between 18°C and 21°C. That is cool: fine for a quick swim, many people find it chilly.
Average20°CCool
Usual range18°C–21°C80% of readings
vs April+1.6°warmer
vs June+3.2°warmer next month
Through the year
Monthly averages 2023–2025. Water at 22°C or warmer: June–November.
May in recent years
| 2023 | 19°C |
|---|---|
| 2024 | 20°C |
| 2025 | 20°C |
Nearby in May
Beaches in Kos
8 of 16 beaches have an Excellent EU water-quality grade. See which ones are calm today.