Current sea water temperature:
+38.5°F
| Minimum sea water temperature in December: | 43.5°F |
| Maximum sea water temperature in December: | 33.3°F |
| Average sea water temperature in December: | 38.7°F |
| more information | |
14 days
forecast
forecast
| Helsinki |
monthly
weather
weather
| Helsinki |
Sea water temperature for the last 10 days:
| December 30 | 38.5°F | December 25 | 38.5°F |
| December 29 | 38.7°F | December 24 | 39.2°F |
| December 28 | 38.3°F | December 23 | 39.9°F |
| December 27 | 37.9°F | December 22 | 39.6°F |
| December 26 | 37.8°F | December 21 | 39.0°F |
Monthly sea water temperature, °F
When is the warmest sea in Helsinki?
Based on the data about daily sea water temperature for the last three years the warmest sea in Helsinki was noticed in August, July and September.
Monthly Sea Temperatures in Helsinki, °F
Sea water temperature in August, °F
Show year:
2025
2024
2023
The average sea water temperature in August of 2025 was 63.8°F. The highest and lowest sea temperatures during the month were 73.9°F and 56.5°F.
Sea water temperature in July, °F
Show year:
2025
2024
2023
The average sea water temperature in July of 2025 was 63.2°F. The highest and lowest sea temperatures during the month were 74.5°F and 54.0°F.
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.
current
weather
weather
| Helsinki |
weather in
January
January
| Helsinki |
Best time for vacation in Helsinki
Helsinki on a weather map
Places in Finland:
Name
°F
24 Hours Forecast
Helsinki
Local time: 03:43
December 31, wednesday
0600
19°F
S
19 mph
19 mph
0900
18°F
S
18 mph
18 mph
1200
19°F
S
17 mph
17 mph
1500
18°F
S
15 mph
15 mph
1800
18°F
S
12 mph
12 mph
2100
16°F
S
11 mph
11 mph
January 01, thursday
0000
16°F
S
9 mph
9 mph
0300
16°F
SE
6 mph
6 mph
