Lake Hallwil
Lake Hallwil is a Swiss lake (Aargau, Lucerne) at 449 m, covering 10 km² with a maximum depth of 47 m. Typical winds: Westwind, Bise. Main shores and access points: Meisterschwanden, Beinwil am See, Seengen, Birrwil, Mosen. The weather above is computed over the middle of the lake; the “Wind on the lake” section details hourly speed, gusts and direction — for sailing, windsurfing, paddling, fishing or swimming.
Climate of Lake Hallwil: 1991–2020 normals
In Lake Hallwil (449 m), the mean annual temperature is 9.8 °C. The warmest month is July (19.2 °C on average) and the coldest January (1.0 °C). About 1008 mm of precipitation falls per year, peaking in August (114 mm) with a minimum in February (56 mm). The sun shines for about 1549 hours a year, mostly in July (225 h). On average there are 77 frost days and 13 hot days (≥ 30 °C) per year. The mean monthly maximum reaches 32.6 °C and the absolute minimum −8.7 °C.
Mean monthly precipitation (mm) — bar height relative to the wettest month.
| Month | Mean T | Abs. max | Abs. min | Precip. (mm) | Sunshine (h) | Frost days | Summer days |
|---|---|---|---|---|---|---|---|
| Jan | 1.0 °C | 11.2 °C | −8.7 °C | 64 | 41 | 20 | 0 |
| Feb | 1.7 °C | 13.5 °C | −8.2 °C | 56 | 74 | 18 | 0 |
| Mar | 5.7 °C | 18.9 °C | −4.9 °C | 63 | 133 | 11 | 0 |
| Apr | 9.6 °C | 23.5 °C | −1.6 °C | 73 | 169 | 2 | 1 |
| May | 13.8 °C | 27.6 °C | 2.7 °C | 110 | 183 | 0 | 5 |
| Jun | 17.5 °C | 31.3 °C | 6.6 °C | 106 | 205 | 0 | 12 |
| Jul | 19.2 °C | 32.6 °C | 9.0 °C | 113 | 225 | 0 | 17 |
| Aug | 18.6 °C | 31.6 °C | 8.4 °C | 114 | 208 | 0 | 15 |
| Sep | 14.4 °C | 26.7 °C | 4.4 °C | 79 | 151 | 0 | 5 |
| Oct | 10.0 °C | 21.6 °C | 0.4 °C | 78 | 86 | 1 | 0 |
| Nov | 4.8 °C | 15.4 °C | −4.0 °C | 71 | 43 | 8 | 0 |
| Dec | 1.7 °C | 11.8 °C | −7.9 °C | 82 | 31 | 17 | 0 |
| Year | 9.8 °C | 32.6 °C | −8.7 °C | 1008 | 1549 | 77 | 55 |
Source: MeteoSwiss open data (1991–2020 normals) — stations Buchs / Aarau (16 km, 387 m), Gösgen (21 km, 380 m), Cham (21 km, 443 m), adjusted to the elevation of Lake Hallwil (449 m) using a 0.55 °C/100 m lapse rate. Indicative, rounded values.
Swiss lakes
- Weather Lake Sempach (16 km · 504 m)
- Weather Lake Zug (26 km · 413 m)
- Weather Lake Ägeri (35 km · 724 m)
- Weather Lake Greifen (36 km · 435 m)
- Weather Lake Lucerne (36 km · 434 m)
- Weather Lake Zurich (36 km · 406 m)
Nearby municipalities
- Weather Beinwil am See (2 km)
- Weather Fahrwangen (2 km)
- Weather Meisterschwanden (2 km)
- Weather Birrwil (3 km)
- Weather Schongau (3 km)
- Weather Aesch (LU) (3 km)
- Weather Reinach (AG) (4 km)
- Weather Leimbach (AG) (4 km)
Swiss lakes Weather Beinwil am See
Frequently asked questions about the weather: Lake Hallwil
What is the wind like on Lake Hallwil today?
The “Wind on the lake” section shows hourly average wind speed, gusts and direction for the next 24 hours, computed over the lake (449 m).
Can you swim in Lake Hallwil?
In summer (June to September) lowland lakes usually reach 18–24 °C at the surface; there are many public beaches and lidos. Check the air temperature, sunshine and UV index above to pick your slot.
What are the typical winds on Lake Hallwil?
Characteristic winds: Westwind, Bise. Storm warnings on Swiss lakes are signalled by flashing lights (40 flashes/min = caution, 90 = storm).
What is the warmest month in Lake Hallwil?
The warmest month in Lake Hallwil is July, averaging 19.2 °C (1991–2020 normal). The coldest is January at 1.0 °C.
How much does it rain in Lake Hallwil per year?
Lake Hallwil receives about 1008 mm of precipitation a year. The wettest month is August (114 mm), the driest February (56 mm).
When is the best time to visit Lake Hallwil?
For warmth and sunshine: July (19.2 °C on average, 225 h of sun). The coldest month is January (1.0 °C). Check the 15-day forecast above for your dates.