Tinnsjå Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Tinnsjå Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Tinnsjå Lake today is 11.5°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
❌ As of today, the minimum water temperature ranges from 50°F (10°C) to 54°F (12°C). The water is slightly warmer, but still cool for most people. Swimming in such conditions is possible, but for most people, the time spent in the water should be limited to avoid hypothermia. Even experienced swimmers may feel discomfort if they stay in the water for too long. To improve comfort and safety, a wetsuit can be used. It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| SEP 14 | 12.8°C | 18.0°C | |
| SEP 15 | 12.6°C | 18.0°C | |
| SEP 16 | 12.4°C | 18.0°C | |
| SEP 17 | 12.4°C | 18.0°C | |
| SEP 18 | 12.5°C | 18.0°C | |
| SEP 19 | 11.8°C | 18.0°C | |
| SEP 20 | 11.2°C | 18.0°C | |
| SEP 21 | 11.5°C | 18.0°C | |
| SEP 22 | 18.0°C | 11.8°C | |
| SEP 23 | 18.0°C | 12.2°C | |
| SEP 24 | 18.0°C | 12.5°C | |
| SEP 25 | 18.0°C | 12.8°C | |
| SEP 26 | 18.0°C | 13.1°C | |
| SEP 27 | 18.0°C | 13.5°C | |
| SEP 28 | 18.0°C | 13.8°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 0°C | 3°C | 6°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 4°C | 7°C |
| April | 1°C | 6°C | 11°C |
| May | 5°C | 12°C | 18°C |
| June | 9°C | 17°C | 24°C |
| July | 16°C | 22°C | 27°C |
| August | 15°C | 21°C | 27°C |
| September | 12°C | 18°C | 23°C |
| October | 7°C | 11°C | 14°C |
| November | 3°C | 7°C | 10°C |
| December | 0°C | 4°C | 7°C |
Tinnsjå Lake: Water Temperature by Location
Tinnsjå Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Tinnsjå is a large, very deep lake in Telemark County whose surface water temperatures vary markedly with the seasons. In high summer the surface typically warms to roughly 15–20 °C (59–68 °F), sometimes reaching low 20s °C on warm, calm days. Late spring sees cooler conditions around 2–10 °C (36–50 °F) as the lake stratifies, and early autumn temperatures commonly fall in the 6–12 °C range (43–54 °F) as cooling begins. In winter the surface can be near freezing, about 0–4 °C (32–39 °F), and parts of the lake may ice over in cold years. Because Tinnsjå is very deep, the hypolimnion (deep water) stays close to about 4 °C (39 °F) year-round, so temperatures drop quickly with depth.
Swimming in Tinnsjå is generally allowed and practiced, particularly in summer when surface temperatures are comfortable for bathing. Local beaches, piers and sheltered bays are the usual places to swim. However, swimmers should be aware of risks: very cold deep water, sudden temperature changes, steep drop-offs, boat traffic and sometimes limited rescue services. Ice swimming is done by experienced people in winter but is hazardous for the unprepared. As with any large lake, using life jackets, staying near shore, and checking local conditions are sensible precautions.