The Slovenia resorts with the warmest sea water temperature in October are Portoroz, Piran and Strunjan.
Below you can see a list of all popular Slovenia resorts and information about sea water temperature in October for the last two years.
| Resort Name | October 2026 | October 2025 | October 2024 |
|---|---|---|---|
| Portoroz | 73.2°F | 69.0°F | 69.0°F |
| Piran | 73.2°F | 69.0°F | 69.0°F |
| Strunjan | 72.9°F | 68.9°F | 68.9°F |
| Isola | 72.7°F | 68.8°F | 68.8°F |
| Koper | 72.7°F | 68.8°F | 68.7°F |
| Cerkno | 70.9°F | 67.3°F | 67.3°F |
| Bohinjsko Jezero | 70.7°F | 67.1°F | 67.3°F |
| Dolenjske Toplice | 68.6°F | 67.1°F | 66.9°F |
Please see following sea water temperature averages charts for the warmest Slovenia resorts in October.
You can also get the same information for the every other month of the year when the average sea water temperature is greater then 70°F.
Slovenia Resorts:
NAME
F°
| Bled |  |
+40 |
| Bohinjsko Jezero | |
+40 |
| Bovec |  |
+44 |
| Cerkno | |
+42 |
| Dolenjske Toplice |  |
+48 |
| Isola | |
+54 |
| Koper | |
+54 |
| Kranjska Gora | |
+40 |
| Ljubljana |  |
+46 |
| Maribor | |
+48 |
| Moravske Toplice | |
+46 |
| Piran | |
+54 |
| Portoroz | |
+54 |
| Rogaska Slatina | |
+48 |
| Strunjan | |
+54 |
