Current Sea Water Temperature:
+83.2°F
| Maximum Sea Water Temperature in September: | 86.2°F |
| Minimum Sea Water Temperature in September: | 71.0°F |
| Average water temperature in September: | 76.6°F |
| detailed information | |
Sea Water Temperature for the Last 10 Days:
| September 08 | 83.2°F | September 03 | 84.2°F |
| September 07 | 83.6°F | September 02 | 84.4°F |
| September 06 | 84.0°F | September 01 | 85.0°F |
| September 05 | 84.2°F | August 31 | 85.0°F |
| September 04 | 84.0°F | August 30 | 85.0°F |
When is the Warmest Sea for Koper?
According to our data for the last three years for Koper the highest average sea water temperature was in August, July and September.
Average Water Temperature by Month, °F
Sea Water Temperature in August
The average sea surface temperature in August 2026 for Koper was 84.8°F. The maximum and minimum values were 83.0°F and 87.6°F respectively.
Sea Water Temperature in July
The average sea surface temperature in July 2026 for Koper was 82.8°F. The maximum and minimum values were 79.8°F and 87.6°F respectively.
Sea Water Temperature in September
The average sea surface temperature in September 2025 for Koper was 78.0°F. The maximum and minimum values were 75.6°F and 80.6°F respectively.
Slovenia Resorts:
NAME
F°
| Bled |  |
+62 |
| Bohinjsko Jezero | |
+62 |
| Bovec | |
+74 |
| Cerkno | |
+64 |
| Dolenjske Toplice | |
+74 |
| Isola | |
+76 |
| Koper | |
+76 |
| Ljubljana | |
+72 |
| Maribor | |
+76 |
| Moravske Toplice | |
+78 |
| Piran | |
+76 |
| Portoroz | |
+76 |
| Rogaska Slatina | |
+72 |
| Smarjeske Toplice | |
+74 |
| Strunjan | |
+76 |
Countries:
NAME
POPULARITY
24 Hours Weather Forecast
Koper
Local time: 21:44
09 sep, wednesday
| 0000 |  |
72°F | W 4 mph |
| 0300 | |
68°F | W 2 mph |
| 0600 | |
66°F | NW 5 mph |
| 0900 |  |
72°F | W 4 mph |
| 1200 | |
76°F | W 4 mph |
| 1500 | |
84°F | N 9 mph |
| 1800 | |
78°F | NE 9 mph |
| 2100 | |
68°F | NW 6 mph |