Measurements:
°C
°F
Rennes
38°F
E 15 mph
Feels like: 30°F
Precip: 79%
World Resorts France Rennes Weather

Rennes Sea Water Temperature

Current Sea Water Temperature:
+47.8°F
Maximum Sea Water Temperature in January: 52.8°F
Minimum Sea Water Temperature in January: 45.8°F
Average water temperature in January: 48.4°F

Sea Water Temperature for the Last 10 Days:

January 09 47.8°F January 04 48.2°F
January 08 48.0°F January 03 48.2°F
January 07 48.0°F January 02 48.4°F
January 06 48.2°F January 01 48.2°F
January 05 48.4°F December 31 48.6°F

When is the Warmest Sea for Rennes?

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

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 Rennes was 69.2°F. The maximum and minimum values were 67.4°F and 70.2°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Rennes was 66.6°F. The maximum and minimum values were 64.2°F and 68.8°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Rennes was 67.4°F. The maximum and minimum values were 65.2°F and 68.6°F respectively.

Best Time to Visit Rennes
The most sunny months:
August 12 days
July 12 days
September 11 days
The most warm months:
August 76.8 °F
July 76.5 °F
June 71.9 °F
Warmest sea temperature:
August 67.6 °F
September 66.5 °F
July 65.7 °F
The most cold months:
January 45.7 °F
February 47.7 °F
December 48.5 °F
The most rainy months:
June 5 days
April 4 days
November 3 days
The most windy months:
February 11 mph
December 11 mph
March 10 mph

Rennes on the Weather Map

France Resorts:
NAME
Annecy +26
Antibes +46
Biarritz +50
Bordeaux +46
Cannes +46
Chamonix +12
Corsica +48
Etretat +44
Marseilles +42
Menton +48
Montpellier +44
Nice +40
Paris +40
Saint-Tropez +44
Toulouse +40
24 Hours Weather Forecast
Rennes
Local time: 03:28
10 jan, saturday
0600 40°F
SE
14 mph
0900 38°F
E
13 mph
1200 44°F
SE
16 mph
1500 46°F
SE
16 mph
1800 38°F
SE
8 mph
2100 34°F
SE
6 mph
11 jan, sunday
0000 34°F
S
1 mph
0300 32°F
NW
5 mph