Reservoir · Norway
Tinnsjå
Lake in Notodden and Tinn, Telemark, Norway
- Area
- 51.2km²
- Max depth
- 460m
- Average depth
- 108m
- Elevation
- 192m a.s.l.
- Shoreline
- 95km
- Volume
- 5.5km³
Tinnsjå is a reservoir in Norway. It covers 51.2 km². On average it is 108 m deep, and 460 m at its deepest point. Its surface lies 192 m above sea level.
Plan your visit
Stay, sail and get there
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The water
How warm is Tinnsjå?
The water is warmest in August, around 15 °C at the surface, and coldest in February, around 0 °C. Even at its warmest, the surface stays below 17 °C on average: this is cold water.
The lake usually freezes over for about 54 days a year, from around 12 January to 6 March.
On the shore, afternoons reach 17 °C on average in July and -5 °C in January. The driest month is February (59 mm of rain), the wettest July (146 mm).
Average surface temperature measured by the Landsat 8 satellite between 2013 and 2021 at the point furthest from the shore (98 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 | — | -5 | -11 | 80 | 15 | 1.1 | 12 |
| February | Ice | — | -4 | -11 | 59 | 12 | 2.7 | 12 |
| March | 0 | 1 | -2 | -9 | 59 | 12 | 5.6 | 11 |
| April | 3 | 4 | 3 | -4 | 69 | 13 | 7.8 | 10 |
| May | 6 | 9 | 10 | 1 | 107 | 15 | 7.0 | 10 |
| June | 11 | 13 | 15 | 6 | 118 | 16 | 7.5 | 10 |
| July | 14 | 15 | 17 | 8 | 146 | 18 | 6.7 | 9 |
| August | 15 | 15 | 15 | 7 | 137 | 18 | 5.5 | 9 |
| September | 13 | 14 | 11 | 4 | 111 | 15 | 4.3 | 11 |
| October | 9 | 11 | 4 | -2 | 116 | 17 | 2.5 | 10 |
| November | 5 | 6 | -1 | -6 | 94 | 16 | 1.0 | 11 |
| December | 2 | 3 | -4 | -10 | 77 | 14 | 0.8 | 12 |
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 2.3 years before flowing out.
- Its catchment drains 3,761 km² of land.
- About 76 m³ of water flow out every second, on average.
- Its shoreline is 3.8 times longer than a circle of the same area: plenty of bays and inlets.
Around the shore
What's around Tinnsjå
Counted within 1.5 km of the shoreline in OpenStreetMap, the map anyone can edit.
- —beaches and swimming spots
- 3campsites
Sjøtveit camping, Sandviken Camping, Tinnsjø kro & camping
- 1boat hire and water-sport clubs
- 2marinas and slipways
- 2ferry piers
Tinnoset brygge, Mæl brygge
- 3viewpoints
- —hotels, B&Bs and chalets
- —fishing spots
- 3restaurants and cafés
Nearest airport with scheduled flights: Sandefjord Airport, Torp (TRF), 117 km in a straight line.
Car hire at TRF airport (Sandefjord)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 | -5.3 | -4.4 | -1.5 | 3.3 | 9.8 | 14.8 | 17.0 | 15.2 | 10.7 | 4.0 | -1.3 | -4.3 |
| 2020 | +4.4 | +2.5 | +0.6 | −0.1 | −1.9 | +3.1 | −3.0 | +1.9 | +0.1 | +0.9 | +3.1 | +1.3 |
| 2021 | −4.1 | −2.4 | +0.9 | −1.7 | −0.9 | +2.7 | +1.8 | +0.3 | +1.2 | +2.1 | +1.1 | −2.0 |
| 2022 | +2.7 | +2.1 | +2.2 | +1.2 | +0.3 | +1.1 | −0.4 | +1.7 | +0.1 | +2.0 | +2.1 | −2.9 |
| 2023 | +0.7 | +2.7 | −1.7 | −2.6 | −1.1 | +4.0 | −2.1 | −0.5 | +2.6 | −1.4 | −3.5 | −3.1 |
| 2024 | −1.3 | +0.3 | +0.3 | −2.7 | +4.0 | −0.5 | −0.9 | −0.3 | +2.3 | +2.1 | +1.7 | +2.5 |
| 2025 | +0.6 | +0.9 | +3.6 | +5.4 | +2.1 | −0.3 | +2.4 | +0.1 | +0.3 | +1.3 | +1.2 | +2.7 |
+1 warmer than usual −1 cooler than usual
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 (Q861703) · 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.
