Measurements:
°C
°F
Seinajoki
70°F
SW 3 mph
Feels like: 70°F
Precip: 0%
World Resorts Finland Seinajoki Weather

Seinajoki Sea Water Temperature

Current Sea Water Temperature:
+54.0°F
Maximum Sea Water Temperature in May: 55.8°F
Minimum Sea Water Temperature in May: 29.2°F
Average water temperature in May: 40.0°F

Sea Water Temperature for the Last 10 Days:

May 30 54.0°F May 25 48.8°F
May 29 55.8°F May 24 46.8°F
May 28 52.8°F May 23 48.4°F
May 27 50.8°F May 22 49.0°F
May 26 51.6°F May 21 47.4°F

When is the Warmest Sea for Seinajoki?

According to our data for the last three years for Seinajoki the highest average sea water temperature was in August, July and September.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Seinajoki was 64.8°F. The maximum and minimum values were 59.4°F and 73.6°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Seinajoki was 66.8°F. The maximum and minimum values were 57.4°F and 76.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Seinajoki was 57.4°F. The maximum and minimum values were 51.8°F and 63.2°F respectively.

Best Time to Visit Seinajoki
The most sunny months:
May 11 days
July 11 days
June 10 days
The most warm months:
July 72.5 °F
August 68.4 °F
June 66.9 °F
Warmest sea temperature:
August 63.3 °F
July 62.1 °F
September 56.4 °F
The most cold months:
January 19.0 °F
February 22.4 °F
December 25.6 °F
The most rainy months:
August 6 days
July 5 days
June 4 days
The most windy months:
March 8 mph
December 7 mph
May 7 mph

Seinajoki on the Weather Map

Finland Resorts:
NAME
Espoo +68
Helsinki +64
Imatra +56
Juvaskyla +66
Kemi +46
Koli National Park +58
Kotka +58
Lahti +66
Oulu +58
Pori +66
Porvoo +58
Saariselka +46
Turku +68
Vaasa +58
Vantaa +68
24 Hours Weather Forecast
Seinajoki
Local time: 11:15
30 may, saturday
1200 70°F
SW
3 mph
1500 74°F
SW
4 mph
1800 74°F
SW
4 mph
2100 64°F
S
6 mph
31 may, sunday
0000 52°F
SW
4 mph
0300 52°F
NW
4 mph
0600 52°F
NW
4 mph
0900 62°F
NW
4 mph