In April warmest sea in Finland is usually observed in the following locations: Turku, Seinajoki, Vaasa.
Table below shows the average sea water temperature for marine resorts of Finland in April for the last three years.
| Place name | April 2026 | April 2025 | April 2024 |
|---|---|---|---|
| Turku | 38.3°F | 39.0°F | 34.6°F |
| Seinajoki | 38.2°F | 35.8°F | 31.0°F |
| Vaasa | 37.4°F | 36.9°F | 32.4°F |
| Espoo | 37.2°F | 39.7°F | 35.0°F |
| Vantaa | 37.2°F | 39.1°F | 34.8°F |
| Kotka | 37.1°F | 37.8°F | 34.8°F |
| Helsinki | 37.0°F | 39.3°F | 34.8°F |
| Oulu | 36.3°F | 32.0°F | 29.9°F |
| Lappeenranta | 36.2°F | 35.5°F | 33.8°F |
| Lahti | 36.2°F | 36.3°F | 35.1°F |
| Pori | 36.1°F | 39.9°F | 35.2°F |
| Porvoo | 36.0°F | 38.0°F | 34.7°F |
| Savolinna | 34.6°F | 34.3°F | 33.1°F |
| Juvaskyla | 32.7°F | 32.9°F | 32.6°F |
| Saariselka | 32.5°F | 32.7°F | 32.7°F |
| Imatra | 32.4°F | 33.6°F | 32.4°F |
| Koli National Park | 32.0°F | 32.1°F | 32.1°F |
| Kemi | 31.8°F | 31.8°F | 29.8°F |
Charts below show average sea water temperature for Finland resorts with the warmest sea in April.
You can also check other months of the year to see sea temperature of Finland resorts at that time.
Places in Finland:
Name
°F
