Is it warm enough to swim in Vannes in September? Average water temperature in Vannes in September is 17.9°C and therefore is not suitable for comfortable swimming. The warmest sea in Vannes in September is 21.1°C, and the coldest is 14.9°C. To find out the sea temperature today and in the coming days, go to Current sea temperature in Vannes
To get an accurate forecast for the water temperature in Vannes for any chosen month, compare two years within a 10 year range using the chart below. In addition to the sea water temperature in Vannes, the selected years in the table also show the values of the maximum and minimum temperatures on each of the days of September.
Day | 2025 | 2024 | Min | Max |
---|---|---|---|---|
1 September | 19.4°C | 18.9°C | 17.1°C | 20.3°C |
2 September | 19.1°C | 18.9°C | 17.2°C | 20.6°C |
3 September | 19.5°C | 19.1°C | 17.2°C | 20.3°C |
4 September | 19.1°C | 18.8°C | 17.1°C | 20.3°C |
5 September | 18.7°C | 17.1°C | 20.8°C | |
6 September | 18.4°C | 16.9°C | 20.3°C | |
7 September | 18.6°C | 16.8°C | 20.2°C | |
8 September | 18.3°C | 17°C | 21.1°C | |
9 September | 17.7°C | 16.9°C | 20.9°C | |
10 September | 17.7°C | 16.9°C | 20.7°C | |
11 September | 17.7°C | 16.7°C | 20.5°C | |
12 September | 17.1°C | 16.2°C | 20°C | |
13 September | 17°C | 16°C | 20.3°C | |
14 September | 17.1°C | 16.2°C | 20.1°C | |
15 September | 16.8°C | 16°C | 20.1°C |
Day | 2025 | 2024 | Min | Max |
---|---|---|---|---|
16 September | 17.1°C | 15.6°C | 19.9°C | |
17 September | 16.9°C | 15.1°C | 20.3°C | |
18 September | 17.1°C | 15.2°C | 20.3°C | |
19 September | 17.5°C | 15.1°C | 19.8°C | |
20 September | 17.4°C | 14.9°C | 19.6°C | |
21 September | 17.2°C | 15.1°C | 19.1°C | |
22 September | 17.4°C | 15.6°C | 19.1°C | |
23 September | 17.3°C | 16°C | 18.8°C | |
24 September | 17.2°C | 16°C | 18.7°C | |
25 September | 17.1°C | 15.8°C | 18.8°C | |
26 September | 17°C | 15.5°C | 19°C | |
27 September | 16.6°C | 15.7°C | 18.9°C | |
28 September | 16.6°C | 15.6°C | 18.3°C | |
29 September | 16.5°C | 15.7°C | 18.7°C | |
30 September | 16.4°C | 15.6°C | 19.2°C |
2015 | 2016 | 2017 | 2018 | 2019 |
17.6°C | 18.4°C | 17°C | 17.7°C | 17.9°C |
2020 | 2021 | 2022 | 2023 | 2024 |
18.8°C | 18.9°C | 19.3°C | 19.5°C | 17.5°C |
Chart comparing the height of waves in Vannes in September over the past years. The red line indicates the height of the waves when swimming in the sea is prohibited. To view the current sea conditions, click on the graph.
You can also view information about water temperature for other months by clicking on the month button below