Measurements:
°C
°F
Rennes
62°F
NW 8 mph
Feels like: 62°F
Precip: 39%
World Resorts France Rennes Weather

Rennes Sea Water Temperature

Current Sea Water Temperature:
+67.8°F
Maximum Sea Water Temperature in September: 70.6°F
Minimum Sea Water Temperature in September: 63.2°F
Average water temperature in September: 66.6°F

Sea Water Temperature for the Last 10 Days:

September 28 67.8°F September 23 67.8°F
September 27 68.0°F September 22 68.0°F
September 26 68.6°F September 21 68.4°F
September 25 68.4°F September 20 68.2°F
September 24 68.6°F September 19 68.4°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: 2026 2025 2024

The average sea surface temperature in August 2026 for Rennes was 70.9°F. The maximum and minimum values were 69.2°F and 72.4°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Rennes was 69.1°F. The maximum and minimum values were 67.8°F and 70.6°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Rennes was 69.1°F. The maximum and minimum values were 66.6°F and 71.0°F respectively.

Best Time to Visit Rennes
The most sunny months:
July 13 days
August 12 days
April 10 days
The most warm months:
July 77.3 °F
August 77.2 °F
June 72.5 °F
Warmest sea temperature:
August 67.8 °F
September 66.6 °F
July 65.9 °F
The most cold months:
January 45.8 °F
February 48.0 °F
December 48.5 °F
The most rainy months:
June 5 days
November 3 days
April 3 days
The most windy months:
February 11 mph
December 11 mph
January 10 mph

Rennes on the Weather Map

France Resorts:
NAME
F°
Antibes +74
Bordeaux +68
Cannes +74
Corsica +70
Deauville +64
Etretat +66
Marseilles +74
Menton +76
Montpellier +74
Nice +68
Paris +68
Perpignan +72
Saint-Tropez +74
Toulon +76
Toulouse +68
24 Hours Weather Forecast
Rennes
Local time: 04:39
29 sep, tuesday
0600 62°F
NW
8 mph
0900 64°F
N
10 mph
1200 70°F
N
10 mph
1500 78°F
NW
17 mph
1800 80°F
N
16 mph
2100 68°F
N
9 mph
30 sep, wednesday
0000 68°F
NW
7 mph
0300 74°F
N
16 mph