Average sea water temperature in December:
+37.3°F
| Minimum sea water temperature in December: | 43.0°F |
| Maximum sea water temperature in December: | 31.8°F |
Daily sea water temperature in December, °F
Show year:
2025
2024
2023
The average sea water temperature in December of 2025 was 39.1°F. The highest and lowest sea temperatures during the month were 42.1°F and 36.9°F.
Monthly sea water temperature in Kotka, °F
Which Finland resorts have warmest sea in December?
| Place name | December 2025 | December 2024 |
|---|---|---|
| Espoo | 39.8°F | 38.5°F |
| Vantaa | 39.5°F | 38.2°F |
| Helsinki | 39.5°F | 38.2°F |
| Kotka | 39.1°F | 38.1°F |
| Turku | 38.8°F | 36.7°F |
| Koli National Park | 37.8°F | 36.7°F |
| Porvoo | 37.7°F | 36.5°F |
| Imatra | 37.5°F | 37.0°F |
| Pori | 37.2°F | 35.2°F |
| Juvaskyla | 36.9°F | 35.9°F |
| Lahti | 36.4°F | 35.3°F |
| Savolinna | 36.1°F | 35.6°F |
| Lappeenranta | 35.9°F | 35.4°F |
| Oulu | 34.1°F | 30.9°F |
| Vaasa | 34.0°F | 32.5°F |
| Saariselka | 34.0°F | 33.8°F |
| Seinajoki | 33.1°F | 31.6°F |
| Kemi | 31.9°F | 31.7°F |
Best time for vacation in Kotka
Kotka on a weather map
Places in Finland:
Name
°F
24 Hours Forecast
Kotka
Local time: 22:43
December 31, wednesday
0000
21°F
S
25 mph
25 mph
0300
21°F
S
25 mph
25 mph
0600
21°F
S
24 mph
24 mph
0900
19°F
S
23 mph
23 mph
1200
19°F
S
22 mph
22 mph
1500
19°F
S
21 mph
21 mph
1800
18°F
S
20 mph
20 mph
2100
18°F
S
17 mph
17 mph
