Gelmersee — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Gelmersee, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Gelmersee today is 18.5°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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 |
|---|---|---|---|
| AUG 13 | 20.4°C | 19.5°C | |
| AUG 14 | 20.4°C | 19.5°C | |
| AUG 15 | 20.7°C | 19.5°C | |
| AUG 16 | 20.3°C | 19.5°C | |
| AUG 17 | 20.2°C | 19.5°C | |
| AUG 18 | 20.1°C | 19.5°C | |
| AUG 19 | 18.4°C | 19.5°C | |
| AUG 20 | 18.2°C | 19.5°C | |
| AUG 21 | 19.5°C | 18.6°C | |
| AUG 22 | 19.5°C | 18.6°C | |
| AUG 23 | 19.5°C | 18.7°C | |
| AUG 24 | 19.5°C | 18.7°C | |
| AUG 25 | 19.5°C | 18.8°C | |
| AUG 26 | 19.5°C | 18.8°C | |
| AUG 27 | 19.5°C | 18.9°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 | 1°C | 1°C |
| February | 0°C | 0°C | 0°C |
| March | 0°C | 1°C | 1°C |
| April | 0°C | 5°C | 9°C |
| May | 4°C | 10°C | 16°C |
| June | 7°C | 15°C | 22°C |
| July | 14°C | 19°C | 24°C |
| August | 14°C | 20°C | 25°C |
| September | 9°C | 12°C | 17°C |
| October | 0°C | 5°C | 9°C |
| November | 0°C | 1°C | 6°C |
| December | 0°C | 1°C | 1°C |
Gelmersee: Water Temperature by Location
Gelmersee: Weather Forecast
August 21
August 22
August 23
August 24
August 25
August 26
Location & Local Information
Type: reservoir
Catchment area: 16.0 km2 (6.2 sq mi)
Basin countries: Switzerland
Surface area: 0.645 km2 (0.249 sq mi)
Max. depth: 48 m (157 ft)
Water volume: 13 million cubic metres (11,000 acre⋅ft)
Surface elevation: 1,850 m (6,070 ft)
Gelmersee is a striking turquoise reservoir high above the Haslital, reached via steep alpine terrain. Its elevation of roughly 1,850 m keeps water temperatures low throughout the year. In winter the lake is typically ice-covered, with water close to 0 °C (32 °F). After ice-out in late spring or early summer, temperatures usually remain around 4–7 °C (39–45 °F). During the brief summer window, mainly July and August, the surface may warm to about 8–12 °C (46–54 °F) on calm, sunny days, before cooling quickly again in autumn to below 8 °C (46 °F).
Swimming is not officially prohibited, but it is uncommon and generally not recommended. Gelmersee is used for hydropower, is very deep, and the water remains cold even at the height of summer. Sudden weather changes and limited access points increase risk. Only experienced cold-water swimmers might consider a very short dip in midsummer; for most visitors, the lake is best enjoyed for hiking and scenery rather than swimming.