World Resorts Finland Helsinki Weather

Helsinki Sea Temperature in September

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.

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

Sunniest months:
June 15 days
July 15 days
May 14 days
Warmest months:
July 68.7 °F
August 67.1 °F
June 63.3 °F
Warmest sea temp:
August 63.2 °F
July 61.9 °F
September 58.8 °F
Coldest months:
January 28.4 °F
February 29.1 °F
December 33.8 °F
Rainiest months:
August 5 days
July 4 days
October 4 days
Windiest months:
December 12.6 mph
November 12.0 mph
January 11.8 mph

Helsinki on a weather map

Helsinki
+32°F
S 28 mph
Feels like: +18°F
Precip.: 0%
Places in Finland:
Name
°F
+30°F
+32°F
+25°F
+34°F
+32°F
+30°F
+25°F
+32°F
+32°F
+18°F
+32°F
+32°F
+32°F
+32°F
+27°F
24 Hours Forecast
Helsinki
Local time: 03:39
December 28, sunday
0600
30°F
S
26 mph
0900
28°F
S
23 mph
1200
30°F
S
20 mph
1500
30°F
SE
15 mph
1800
30°F
E
9 mph
2100
32°F
E
8 mph
December 29, monday
0000
32°F
E
8 mph
0300
34°F
SE
12 mph
Units of measurement: °C / °F