Average sea water temperature in September:
+73.3°F
| Minimum sea water temperature in September: | 81.1°F |
| Maximum sea water temperature in September: | 67.3°F |
Daily sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 73.6°F. The highest and lowest sea temperatures during the month were 75.6°F and 71.1°F.
Monthly sea water temperature in Cerkno, °F
Which Slovenia resorts have warmest sea in September?
| Place name | September 2025 | September 2024 |
|---|---|---|
| Portoroz | 75.3°F | 75.9°F |
| Piran | 75.3°F | 75.9°F |
| Strunjan | 75.2°F | 75.8°F |
| Koper | 75.2°F | 75.5°F |
| Isola | 75.1°F | 75.6°F |
| Cerkno | 73.6°F | 74.6°F |
| Bohinjsko Jezero | 73.3°F | 74.5°F |
| Dolenjske Toplice | 71.7°F | 72.0°F |
Best time for vacation in Cerkno
Cerkno on a weather map
Places in Slovenia:
Name
°F
24 Hours Forecast
Cerkno
Local time: 22:03
December 30, tuesday
0000

32°F
W
2 mph
2 mph
0300

32°F
W
3 mph
3 mph
0600

34°F
W
4 mph
4 mph
0900

36°F
SW
6 mph
6 mph
1200

37°F
W
14 mph
14 mph
1500

34°F
W
14 mph
14 mph
1800

28°F
W
12 mph
12 mph
2100

27°F
W
9 mph
9 mph

























