Reservoir · Switzerland
Sihlsee
Body of water
- Area
- 9.9km²
- Max depth
- 23m
- Average depth
- 9.7m
- Elevation
- 881m a.s.l.
- Shoreline
- 22km
- Volume
- 0.097km³
Sihlsee is a reservoir in Switzerland. It covers 9.9 km². On average it is 9.7 m deep, and 23 m at its deepest point. Its surface lies 881 m above sea level.
Plan your visit
Stay, sail and get there
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The water
How warm is Sihlsee?
The water is warmest in July, around 22 °C at the surface, and coldest in January, around 0 °C. The surface averages 20 °C or more from July to August: comfortable for most swimmers.
The lake usually freezes over for about 63 days a year, from around 27 December to 27 February.
On the shore, afternoons reach 20 °C on average in July and 0 °C in January. The driest month is February (80 mm of rain), the wettest August (190 mm).
Average surface temperature measured by the Landsat 8 satellite between 2013 and 2021 at the point furthest from the shore (133 readings). Shallow bays and beaches are often warmer.
From above
The whole lake from space
Month by month
The year at the lake, month by month
Not a forecast: these are averages over many years. Water is the 2013–2021 average; air, rain, sun and wind are the 1991–2020 average.
Water: 2013–2021 averageClimate: 1991–2020 average
| Month | Water°C | Water high°C | Air high°C | Air low°C | Rainmm | Rainy daysdays | Sunh/day | Windkm/h |
|---|---|---|---|---|---|---|---|---|
| January | Ice | — | 0 | -8 | 101 | 14 | 2.5 | 9 |
| February | Ice | — | 0 | -8 | 80 | 12 | 3.8 | 9 |
| March | 3 | 5 | 5 | -4 | 102 | 15 | 5.3 | 9 |
| April | 8 | 11 | 10 | 1 | 107 | 16 | 6.5 | 8 |
| May | 14 | 17 | 14 | 5 | 163 | 19 | 6.7 | 8 |
| June | 19 | 21 | 18 | 10 | 176 | 20 | 8.0 | 7 |
| July | 22 | 22 | 20 | 12 | 173 | 19 | 8.1 | 7 |
| August | 21 | 22 | 20 | 11 | 190 | 18 | 7.3 | 7 |
| September | 18 | 20 | 16 | 7 | 124 | 15 | 6.0 | 7 |
| October | 13 | 16 | 12 | 3 | 110 | 14 | 4.2 | 8 |
| November | 7 | 10 | 5 | -2 | 103 | 15 | 2.4 | 8 |
| December | 2 | 4 | 0 | -7 | 106 | 15 | 2.0 | 9 |
Water: LakeTEMP (Landsat 8, 2013–2021). Air, rain, sun and wind: NASA POWER, 1991–2020 averages. A rainy day has at least 1 mm of rain. Sunshine hours are derived from measured solar radiation.
Size & depth
How big, how deep
- On average, water stays in the lake for about 7 months before flowing out.
- Its catchment drains 153 km² of land.
- About 5.7 m³ of water flow out every second, on average.
Around the shore
What's around Sihlsee
Counted within 1.5 km of the shoreline in OpenStreetMap, the map anyone can edit.
- 1beaches and swimming spots
- 4campsites
Hotel Allegro, Stellplatz Friedhof, Camping Euthal, Grüene Aff
- 1boat hire and water-sport clubs
Rampe
- 5marinas and slipways
- 6ferry piers
Willerzell, Anlegestelle Grüne Aff, Staumauer, Segelplatz, Nügüetli and 1 more
- 7viewpoints
Friherrenberg, Vogelherd and 5 more
- 3hotels, B&Bs and chalets
Drei Könige, Post, Allegro
- —fishing spots
- 19restaurants and cafés
Towns on the shore
- Einsiedeln15,867 people
- Unteriberg2,307 people
Nearest airport with scheduled flights: Zürich Airport (ZRH), 39 km in a straight line.
Car hire at ZRH airport (Zurich)Discover Cars · Affiliate linkOpenStreetMap is built by volunteers: when a number is low, it may just mean nobody has mapped it yet.
Recent years
How each month compared
Afternoon high on the shore. The first row is the reference, the 1991–2020 average in °C; the years below show the difference from it: warmer in orange, cooler in blue.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1991–2020 average | -0.5 | 0.4 | 4.7 | 9.7 | 14.0 | 18.2 | 19.8 | 19.5 | 15.5 | 11.5 | 5.1 | 0.4 |
| 2020 | +2.9 | +3.4 | +0.8 | +3.5 | +0.9 | −1.9 | +0.4 | +0.6 | +1.4 | −2.5 | +3.1 | −0.6 |
| 2021 | −1.7 | +1.5 | −0.6 | −2.6 | −3.0 | +1.9 | −0.7 | −1.7 | +2.1 | −0.6 | −0.6 | +0.8 |
| 2022 | +1.2 | +1.7 | +2.4 | −0.1 | +2.2 | +3.1 | +2.2 | +1.6 | −0.5 | +4.3 | +1.3 | +1.1 |
| 2023 | +0.5 | +3.2 | +1.9 | −1.8 | −0.1 | +1.8 | +1.6 | +1.4 | +4.8 | +3.5 | −0.8 | +1.5 |
| 2024 | +1.5 | +5.3 | +2.0 | −0.7 | −0.1 | +0.1 | +1.5 | +3.1 | ±0.0 | +1.5 | +2.1 | +1.2 |
| 2025 | +1.7 | +3.2 | +2.0 | +2.7 | −0.1 | +4.0 | −0.9 | +1.6 | +0.8 | −0.8 | ±0.0 | +2.6 |
+1 warmer than usual −1 cooler than usual
Nearby
More lakes nearby
About these numbers
| Outline, area, depth, volume | HydroLAKES v1.0 (Messager et al. 2016) · CC BY 4.0 |
|---|---|
| Water temperature and ice | LakeTEMP v1 (Korver et al. 2024), Landsat 8 2013–2021 · CC BY 4.0 |
| Air, rain, sun, wind | NASA POWER, 1991–2020 · public domain |
| Names and description | Wikidata (Q688846) · CC0 |
| Around the shore | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
Every figure is an average or a count from a public dataset. Licences and methods: data sources.
