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Landes · France

Lac de Biscarrosse Water Temperature Today

Lac de Biscarrosse in Landes, France warms into the mid-20s °C for reliable summer swimming, and drops close to single digits in winter.

In August Lac de Biscarrosse averages about 25°C at the surface, peaking near 25°C in July, August, September and dropping to roughly 8°C at its coldest.

Water temperature estimate
25.0°Chot
August climatology for this lake · Excellent
Typical in August
25.0°C
Air temperature
Wind
UV index

Lake surface temperatures are modelled from long-term monthly averages and refined with live air temperature, wind and UV. Sea temperatures elsewhere on SwimTemperature come from measured marine model data.

Lac de Biscarrosse water temperature by month

MonthAverage water temperatureSwimming
January9.1°Ccold
February8.0°Ccold
March9.1°Ccold
April12.3°Ccool
May16.5°Cmild
June20.8°Cwarm
July23.9°Cwarm
August25.0°Chot
September23.9°Cwarm
October20.8°Cwarm
November16.5°Cmild
December12.3°Ccool

Lac de Biscarrosse swim conditions FAQ

Best time to swim, water safety and the temperature thresholds that matter for open-water swimming in Lac de Biscarrosse.

Best time to swim

The warmest water in Lac de Biscarrosse is in July, August, September, around 25.0°C.

The comfortable swim season — 18°C or warmer — covers June, July, August, September, October. Right now (August) expect about 25.0°C.

Within a day, the surface is warmest in the late afternoon, while early morning is calmest and quietest for boat traffic.

Water safety tips

  • Enter Lac de Biscarrosse slowly and let your breathing settle before swimming out — cold shock is the biggest single risk in fresh water.
  • Swim parallel to the shore rather than out and back, so you are never far from a safe exit.
  • Lakes have no lifeguard on most shorelines: swim with a partner and use a bright tow float so boats can see you.
  • Check for boat traffic, sudden drop-offs, weed beds and submerged obstacles before your first swim of the season.
  • Deep lakes stay cold below the surface even in a heatwave — expect a sharp thermocline a metre or two down.
  • After heavy rain or during a warm calm spell, avoid swallowing water: runoff and algal blooms can cause illness.
  • Get warm and dressed quickly after cold swims — afterdrop peaks 10–30 minutes out of the water.

Temperature thresholds

WaterFeelsWhat to do
24°C and aboveWarmComfortable for long swims in swimwear. Watch UV and stay hydrated.
20–23°CPleasantIdeal open-water conditions for most swimmers; no neoprene needed.
18–19°CFreshFine for 30–60 minutes; a shorty wetsuit extends comfort.
14–17°CCoolCold-water rules apply. A 3/2mm full suit is sensible.
10–13°CColdLimit to short swims, 4/3mm suit, gloves and boots; never swim alone.
Below 10°CVery coldCold shock and swim failure risk. Acclimatised swimmers only, minutes not hours, with supervision.

At today's estimate of 25.0°C, Lac de Biscarrosse rates as hotExcellent.

What is the water temperature of Lac de Biscarrosse right now?

In August the surface of Lac de Biscarrosse averages about 25°C. The reading at the top of this page refines that monthly average with today's live air temperature, wind and UV.

Can you swim in Lac de Biscarrosse?

Yes. Lac de Biscarrosse reaches 18°C or warmer in June, July, August, September, October, which most swimmers find comfortable without neoprene. Outside those months treat it as cold-water swimming.

When is the best time to swim in Lac de Biscarrosse?

July, August, September offer the warmest water, around 25°C. Within the day, late afternoon is usually warmest at the surface, while early morning is calmest with the least boat traffic — the usable swim season runs across June, July, August, September, October.

How cold does Lac de Biscarrosse get in winter?

The coldest month averages roughly 8°C at the surface.

What water temperature is safe to swim in?

Above 20°C is comfortable for most people, 18–20°C is fresh but fine for shorter swims, 14–17°C calls for a wetsuit, and below 10°C is experienced cold-water swimmers only — minutes rather than hours, always with someone watching.

Do I need a wetsuit in Lac de Biscarrosse?

Based on the monthly averages: no wetsuit needed at 22°C or above, a shorty from about 18°C, a 3/2mm full suit from 14°C, and 4/3mm with gloves and boots below 14°C. Lac de Biscarrosse peaks near 25°C and bottoms out near 8°C.

Is Lac de Biscarrosse safe to swim in?

Most of the year, yes, provided you pick a known entry point, swim parallel to the shore with a partner, and check local signage. Avoid swimming after heavy rain or during visible algal blooms, and remember lake shorelines are rarely lifeguarded.

Compare lake temperatures

Pick up to 4 lakes to compare today's water temperature and the next seven days.

Warmest today
Lac de Biscarrosse · 25.0°C
Lac de BiscarrosseLac de SanguinetLac de Lacanau
LakeTodayNext 7 days
Lac de BiscarrosseFrance25.0°ChotLoading forecast…
Lac de SanguinetFrance25.0°ChotLoading forecast…
Lac de LacanauFrance24.0°ChotLoading forecast…

Water temperatures are modelled from long-term monthly averages for each lake and refined daily with forecast air temperature, so the seven-day column shows the expected trend rather than a measured buoy reading.

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