Average sea water temperature in September:
+58.8°F
| Minimum sea water temperature in September: | 65.8°F |
| Maximum sea water temperature in September: | 50.7°F |
Daily sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 59.5°F. The highest and lowest sea temperatures during the month were 63.3°F and 54.0°F.
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Monthly sea water temperature in Helsinki, °F
Which Finland resorts have warmest sea in September?
| Place name | September 2025 | September 2024 |
|---|---|---|
| Kotka | 61.4°F | 64.4°F |
| Lappeenranta | 61.2°F | 64.4°F |
| Lahti | 60.6°F | 62.4°F |
| Turku | 60.5°F | 61.9°F |
| Savolinna | 60.1°F | 62.9°F |
| Vantaa | 59.5°F | 61.9°F |
| Helsinki | 59.5°F | 61.7°F |
| Juvaskyla | 59.5°F | 61.0°F |
| Imatra | 59.4°F | 62.4°F |
| Espoo | 59.3°F | 61.8°F |
| Porvoo | 59.1°F | 61.9°F |
| Koli National Park | 59.1°F | 61.5°F |
| Vaasa | 57.7°F | 58.8°F |
| Pori | 57.3°F | 60.1°F |
| Seinajoki | 56.7°F | 58.0°F |
| Oulu | 56.6°F | 58.0°F |
| Kemi | 56.2°F | 58.2°F |
| Saariselka | 53.1°F | 54.0°F |
Best time for vacation in Helsinki
Helsinki on a weather map
Places in Finland:
Name
°F
24 Hours Forecast
Helsinki
Local time: 23:37
December 18, thursday
0000
39°F
E
15 mph
15 mph
0300
39°F
E
14 mph
14 mph
0600
37°F
E
8 mph
8 mph
0900
36°F
E
7 mph
7 mph
1200
37°F
NE
6 mph
6 mph
1500
37°F
NE
8 mph
8 mph
1800
39°F
N
10 mph
10 mph
2100
39°F
NE
13 mph
13 mph
