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Bavaria · Germany

Lake Sylvenstein Water Temperature Today

Lake Sylvenstein in Bavaria, Germany is swimmable in high summer, brisk either side of it, and drops close to single digits in winter.

In August Lake Sylvenstein averages about 19°C at the surface, peaking near 19°C in July, August, September and dropping to roughly 3°C at its coldest.

Water temperature estimate
19.0°Cmild
August climatology for this lake · Good
Typical in August
19.0°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.

Lake Sylvenstein water temperature by month

MonthAverage water temperatureSwimming
January4.1°Ccold
February3.0°Ccold
March4.1°Ccold
April7.0°Ccold
May11.0°Ccool
June15.0°Cmild
July17.9°Cmild
August19.0°Cmild
September17.9°Cmild
October15.0°Cmild
November11.0°Ccool
December7.0°Ccold

Lake Sylvenstein swim conditions FAQ

Best time to swim, water safety and the temperature thresholds that matter for open-water swimming in Lake Sylvenstein.

Best time to swim

The warmest water in Lake Sylvenstein is in July, August, September, around 19.0°C.

The comfortable swim season — 18°C or warmer — covers August. Right now (August) expect about 19.0°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 Lake Sylvenstein 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 19.0°C, Lake Sylvenstein rates as mildGood.

What is the water temperature of Lake Sylvenstein right now?

In August the surface of Lake Sylvenstein averages about 19°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 Lake Sylvenstein?

Yes. Lake Sylvenstein reaches 18°C or warmer in August, which most swimmers find comfortable without neoprene. Outside those months treat it as cold-water swimming.

When is the best time to swim in Lake Sylvenstein?

July, August, September offer the warmest water, around 19°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 August.

How cold does Lake Sylvenstein get in winter?

The coldest month averages roughly 3°C at the surface. At that temperature cold shock is a genuine hazard for unacclimatised swimmers.

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 Lake Sylvenstein?

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. Lake Sylvenstein peaks near 19°C and bottoms out near 3°C.

Is Lake Sylvenstein 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
Lake Kochelsee · 22.0°C
Lake SylvensteinLake WalchenseeLake Kochelsee
LakeTodayNext 7 days
Lake SylvensteinGermany19.0°CmildLoading forecast…
Lake WalchenseeGermany20.0°CwarmLoading forecast…
Lake KochelseeGermany22.0°CwarmLoading 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.

Open the full lake comparison tool · See Lake Sylvenstein on the live lake temperature map