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Tennessee · United States

Douglas Lake Water Temperature Today

Douglas Lake in Tennessee, United States stays bath-warm through the summer swim season, and drops close to single digits in winter.

In August Douglas Lake averages about 29°C at the surface, peaking near 29°C in July, August, September and dropping to roughly 8°C at its coldest.

Water temperature estimate
29.0°Ctropical
August climatology for this lake · Excellent
Typical in August
29.0°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.

Douglas Lake water temperature by month

MonthAverage water temperatureSwimming
January9.4°Ccold
February8.0°Ccold
March9.4°Ccold
April13.3°Ccool
May18.5°Cmild
June23.8°Cwarm
July27.6°Ctropical
August29.0°Ctropical
September27.6°Ctropical
October23.8°Cwarm
November18.5°Cmild
December13.3°Ccool

Douglas Lake swim conditions FAQ

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

Best time to swim

The warmest water in Douglas Lake is in July, August, September, around 29.0°C.

The comfortable swim season — 18°C or warmer — covers May, June, July, August, September, October, November. Right now (August) expect about 29.0°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 Douglas Lake 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 29.0°C, Douglas Lake rates as tropicalExcellent.

What is the water temperature of Douglas Lake right now?

In August the surface of Douglas Lake averages about 29°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 Douglas Lake?

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

When is the best time to swim in Douglas Lake?

July, August, September offer the warmest water, around 29°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 May, June, July, August, September, October, November.

How cold does Douglas Lake 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 Douglas Lake?

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. Douglas Lake peaks near 29°C and bottoms out near 8°C.

Is Douglas Lake 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
Douglas Lake · 29.0°C
Douglas LakeNorris LakeFontana Lake
LakeTodayNext 7 days
Douglas LakeUnited States29.0°CtropicalLoading forecast…
Norris LakeUnited States28.0°CtropicalLoading forecast…
Fontana LakeUnited States26.0°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.

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