This data the coastal Hermance water temperature today, tomorrow and the upcoming days. Besides, you can also get information about the weather and surf forecast, as well as the data on sunrise / sunset and moonrise / moonset at a given point on any given day.
Water temperature in Hermance today is 20.3°C. Based on our historical data over a period of ten years, the warmest water in this day in the Lake Geneva near Hermance was recorded in 2022 and was 22.7°C, and the coldest was recorded in 2012 at 18.4°C. Water temperature in Hermance is expected to drop to 19.2°C in the next 10 days. September average water temperature in Hermance is 19.2°C, the minimum temperature is 16.1°C, and the maximum is 23.4°C.
The swimming season in Hermance lasts from July to September. During those months, Hermance water temperature does not drop below 20°C and therefore suitable for comfortable swimming. The average water temperature in Hermance in winter reaches 9.4°C, in spring 11.3°C, in summer the average temperature rises to 20°C, and in autumn it is 16°C.
5 September 2025 |
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today temp |
20.3°C |
4 September 2025 |
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yesterday temp |
20.2°C |
Data in a table show Hermance temperature today (6 September 2025). For more information and forecast for a few days, go to the weather forecast Hermance.
0-3 h | 3-6 h | 6-9 h | 9-12 h |
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11.9°C | 11.6°C | 11.1°C | 15.5°C |
12-15 h | 15-18 h | 18-21 h | 21-24 h |
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20°C | 20.5°C | 17.6°C | 11.1°C |
You may also be interested in other sections of our site for Hermance: Sunrise and Sunset, Tides
These figures shows the average, minimum and maximum monthly water temperature in Hermance. In addition to the table values, the graph below displays of changes average surface temperature during the year. Values are calculated based on the data over the past 10 years. Using them, you can check the water temperature in Hermance on any day of this period that interests you. Click on the month link and you will see a table for each day, or alternatively you can view the temperature curve of the month and select 2 different years you want to compare, either in a table or as a curve
Month | Avr | Min | Max | |
---|---|---|---|---|
January | 9.1°C | 6.9°C | 10.5°C | cold |
Water temperature in Hermance in January | ||||
February | 8.4°C | 6.4°C | 9.3°C | cold |
Water temperature in Hermance in February | ||||
March | 8.8°C | 6.4°C | 10.7°C | cold |
Water temperature in Hermance in March | ||||
April | 11.1°C | 8.1°C | 14.3°C | cold |
Water temperature in Hermance in April | ||||
May | 14°C | 10.9°C | 18.9°C | cold |
Water temperature in Hermance in May | ||||
June | 17.8°C | 12.6°C | 24.1°C | cold |
Water temperature in Hermance in June | ||||
July | 20.9°C | 16.8°C | 24.9°C | warm |
Water temperature in Hermance in July | ||||
August | 21.2°C | 18.1°C | 25.9°C | warm |
Water temperature in Hermance in August | ||||
September | 19.2°C | 16.1°C | 23.4°C | cold |
Water temperature in Hermance in September | ||||
October | 15.8°C | 13.6°C | 19.8°C | cold |
Water temperature in Hermance in October | ||||
November | 12.9°C | 11.1°C | 15°C | cold |
Water temperature in Hermance in November | ||||
December | 10.7°C | 8.6°C | 12.8°C | cold |
Water temperature in Hermance in December |