Measurements:
°C
°F
Kotka
38°F
NE 6 mph
Feels like: 34°F
Precip: 0%
World Resorts Finland Kotka Weather

Kotka Sea Water Temperature

Current Sea Water Temperature:
+40.2°F
Maximum Sea Water Temperature in December: 42.2°F
Minimum Sea Water Temperature in December: 29.8°F
Average water temperature in December: 35.8°F

Sea Water Temperature for the Last 10 Days:

December 04 40.2°F November 29 40.4°F
December 03 40.8°F November 28 40.8°F
December 02 41.2°F November 27 41.0°F
December 01 40.4°F November 26 41.4°F
November 30 41.0°F November 25 41.6°F

When is the Warmest Sea for Kotka?

According to our data for the last three years for Kotka 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 Kotka was 67.1°F. The maximum and minimum values were 60.4°F and 78.8°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Kotka was 66.2°F. The maximum and minimum values were 56.8°F and 79.0°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Kotka was 62.7°F. The maximum and minimum values were 57.2°F and 66.8°F respectively.

Best Time to Visit Kotka
The most sunny months:
July 15 days
June 14 days
May 13 days
The most warm months:
July 68.3 °F
August 67.2 °F
June 61.3 °F
Warmest sea temperature:
August 66.0 °F
July 64.8 °F
September 60.5 °F
The most cold months:
January 24.4 °F
February 24.6 °F
March 30.6 °F
The most rainy months:
October 5 days
August 5 days
December 4 days
The most windy months:
December 14 mph
November 14 mph
October 14 mph

Kotka on the Weather Map

Finland Resorts:
NAME
Espoo +38
Helsinki +38
Juvaskyla +34
Kemi +30
Koli National Park +32
Kotka +38
Lahti +36
Lappeenranta +36
Oulu +34
Pori +38
Saariselka +14
Savolinna +34
Turku +40
Vaasa +38
Vantaa +38
24 Hours Weather Forecast
Kotka
Local time: 09:06
05 dec, friday
1200 40°F
NE
7 mph
1500 40°F
NE
5 mph
1800 38°F
N
6 mph
2100 40°F
N
6 mph
06 dec, saturday
0000 40°F
NW
7 mph
0300 40°F
NW
9 mph
0600 40°F
NW
10 mph
0900 38°F
W
13 mph