In May warmest sea in Slovenia is usually observed in the following locations: Portoroz, Piran, Strunjan.
Table below shows the average sea water temperature for marine resorts of Slovenia in May for the last three years.
| Place name | May 2026 | May 2025 | May 2024 |
|---|---|---|---|
| Portoroz | 62.5°F | 65.3°F | 64.5°F |
| Piran | 62.5°F | 65.3°F | 64.5°F |
| Strunjan | 62.3°F | 65.2°F | 64.3°F |
| Isola | 62.1°F | 65.1°F | 64.1°F |
| Koper | 62.0°F | 64.9°F | 64.1°F |
| Cerkno | 61.3°F | 63.3°F | 63.4°F |
| Bohinjsko Jezero | 61.3°F | 63.2°F | 63.3°F |
| Dolenjske Toplice | 60.8°F | 62.3°F | 64.0°F |
Charts below show average sea water temperature for Slovenia resorts with the warmest sea in May.
You can also check other months of the year to see sea temperature of Slovenia resorts at that time.
Places in Slovenia:
Name
°F
