Lake · Finland
Ähtärinjärvi
Lake in Ähtäri, Finland
- Area
- 53.0km²
- Average depth
- 12m
- Elevation
- 133m a.s.l.
- Shoreline
- 140km
- Volume
- 0.631km³
Ähtärinjärvi is a lake in Finland. It covers 53.0 km². On average it is 12 m deep. Its surface lies 133 m above sea level.
Plan your visit
Stay, sail and get there
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The water
How warm is Ähtärinjärvi?
The water is warmest in July, around 20 °C at the surface, and coldest in January, around 0 °C. It rarely averages 20 °C, but it stays above 17 °C from July to August: brisk, refreshing swimming.
The lake usually freezes over for about 148 days a year, from around 12 November to 8 April.
On the shore, afternoons reach 21 °C on average in July and -6 °C in January. The driest month is March (41 mm of rain), the wettest July (94 mm).
Average surface temperature measured by the Landsat 8 satellite between 2013 and 2021 at the point furthest from the shore (125 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 | — | -6 | -11 | 54 | 13 | 0.5 | 10 |
| February | Ice | — | -5 | -11 | 43 | 11 | 2.2 | 10 |
| March | Ice | — | -1 | -8 | 41 | 11 | 5.6 | 10 |
| April | 2 | 5 | 7 | -2 | 53 | 12 | 6.8 | 9 |
| May | 8 | 12 | 14 | 4 | 66 | 12 | 8.4 | 8 |
| June | 16 | 18 | 18 | 9 | 88 | 15 | 8.5 | 8 |
| July | 20 | 20 | 21 | 12 | 94 | 16 | 8.2 | 7 |
| August | 18 | 20 | 19 | 11 | 84 | 15 | 6.7 | 7 |
| September | 13 | 16 | 14 | 6 | 72 | 13 | 4.1 | 8 |
| October | 6 | 10 | 6 | 1 | 76 | 15 | 1.7 | 8 |
| November | Ice | — | 0 | -3 | 69 | 15 | 0.2 | 9 |
| December | Ice | — | -3 | -8 | 62 | 14 | 0.1 | 10 |
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 8.4 years before flowing out.
- Its catchment drains 300 km² of land.
- About 2.4 m³ of water flow out every second, on average.
- Its shoreline is 5.4 times longer than a circle of the same area: plenty of bays and inlets.
Around the shore
What's around Ähtärinjärvi
Counted within 1.5 km of the shoreline in OpenStreetMap, the map anyone can edit.
- 13beaches and swimming spots
Honkiniemen uimaranta, Suninsalmen uimaranta, Mustaniemen uimaranta and 10 more
- 1campsites
Ähtäri Zoo Camping Mekkoranta
- —boat hire and water-sport clubs
- 7marinas and slipways
Mesikämmenen veneramppi, Suninsalmen veneluiska, Inhanjoki, Suninsalmen satama, Mesikämmenen satama and 2 more
- —ferry piers
- —viewpoints
- 27hotels, B&Bs and chalets
Divers bed & breakfast Rannankylä, Villa Hanhisalo, Tuomarniemen lomatupa, Naava Chalet, Laikka and 22 more
- —fishing spots
- 9restaurants and cafés
Nearest airport with scheduled flights: Jyväskylä Airport (JYV), 90 km in a straight line.
Car hire at KOK airport (Kokkola / Kruunupyy)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 | -6.0 | -5.2 | -1.0 | 6.6 | 14.0 | 18.1 | 21.1 | 19.0 | 13.5 | 5.7 | 0.4 | -3.3 |
| 2020 | +6.6 | +4.9 | +2.8 | −1.6 | −2.6 | +4.3 | −2.8 | +0.1 | +0.8 | +2.0 | +3.2 | +1.4 |
| 2021 | −2.5 | −2.9 | ±0.0 | −0.2 | −0.9 | +4.4 | +2.3 | −1.4 | −2.7 | +1.9 | −0.2 | −3.3 |
| 2022 | +1.1 | +2.5 | +1.0 | −1.0 | −1.1 | +1.9 | −0.6 | +1.7 | −1.7 | +2.6 | −0.3 | −1.6 |
| 2023 | +2.5 | +2.1 | −1.2 | −1.4 | +0.1 | +2.3 | −1.2 | +0.7 | +3.0 | −1.9 | −4.5 | −5.0 |
| 2024 | −3.1 | −0.1 | +0.4 | −3.0 | +3.9 | +2.3 | +0.2 | +1.4 | +2.7 | +2.6 | +1.4 | +1.6 |
| 2025 | +2.4 | +2.6 | +4.0 | +1.4 | −1.6 | −0.9 | +2.8 | −1.1 | +2.2 | +1.7 | +2.1 | +3.3 |
+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 (Q7362010) · 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.
