Lake Serre-Ponçon water temperature and level today
One of the largest reservoirs in Western Europe. It fills in spring to approach its maximum level of 780 m in summer, then drops through autumn and winter.
At a glance
- Surface area
- 28 km²
- Location
- Hautes-Alpes, French Alps
Summer 2026
The water peaked at 22.3 °C. In July and August our readings averaged 21.0 °C.
Is it warm enough to swim?
Above 22 °C the water feels pleasant to almost everyone. Between 18 and 22 °C swimming is fine but refreshing. Below 18 °C a wetsuit helps for longer swims, and below 14 °C it becomes essential for water sports.
Frequently asked questions
What is the water temperature in Lake Serre-Ponçon today?
The temperature is updated daily at the top of this page. In summer 2026 the water reached 22.3 °C, averaging 21.0 °C in July and August.
When is the water warmest in Lake Serre-Ponçon?
Usually from mid-July to late August. The lake warms from May and cools clearly from late September.
What is the water level in Lake Serre-Ponçon today?
Today's level is shown at the top of this page in metres above sea level, with the gap to the lake's reference level. The history shows 30 days, 90 days, 1 year and 3 years.
How can I show this temperature on my website?
With the Lakemetric API: one request with the latitude and longitude of the lake or beach returns the temperature, the level and the reading date. A free key covers one lake or spot.
Other lakes and beaches
Show this temperature on your website
The same data is available through the API: send a GPS point, get the temperature, the level and the reading date as JSON. Free key, no card.