Arth climate — normals and trends
Arth (Switzerland) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 6.7 °C and it receives 1,825 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (15.7 °C on average) and the coldest is January (-2.1 °C). Rainfall peaks in August.
Arth averages 129 frost days, 0 hot days (≥ 30 °C) and 190 rainy days per year.
Arth has warmed by +2.9 °C between 1940 and 2025, or +0.34 °C per decade. This trend is statistically significant.
The number of frost days there went from about 160 to 98 per year over the period.
The hottest day of the period reached 31.1 °C (on 7 July 2015) and the coldest -23.0 °C (on 12 January 1987).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
ArthCanton of Schwyz
- coords
- 47.06°, 8.52°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
6.7°C
Average daily high
10.4°C
Average daily low
3.1°C
Annual rainfall
1,825mm
Sunshine / day
8.7h
Mean relative humidity
79%
Average peak wind
7.4km/h
Seasonal range
17.8°C
Frost days (< 0 °C)
129 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
190 d/yr
Annual snowfall
343.4 cm
Average feels-like high
8.8 °C
Average feels-like low
0.7 °C
Average peak gust
31.7 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
12.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.9 °C
since 1940
+0.3 °C per decade · r² = 0.67 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
31.1 °C
7 July 2015
Coldest day
-23.0 °C
12 January 1987
Wettest day
85 mm
28 July 2019
Windiest day
22.9 km/h
21 October 2014
Strongest gust
140.4 km/h
27 February 1990
Hottest feels-like
34.2 °C
5 July 2015
Coldest feels-like
-27.4 °C
12 January 1987
Snowiest day
31.0 cm
4 April 2019
Sunniest day
15.0 h
5 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 2.6 °C | +2.2 °C | 109 mm | -12 mm |
| Feb | 4.3 °C | +2.1 °C | 41 mm | -74 mm |
| Mar | 8.5 °C | +2.5 °C | 92 mm | -35 mm |
| Apr | 13.1 °C | +3.5 °C | 119 mm | -25 mm |
| May | 15.0 °C | +0.9 °C | 203 mm | +28 mm |
| Jun | 22.9 °C | +5.1 °C | 111 mm | -82 mm |
| Jul | 19.6 °C | -0.4 °C | 310 mm | +112 mm |
| Aug | 21.8 °C | +2.2 °C | 241 mm | +38 mm |
| Sep | 16.5 °C | +0.1 °C | 232 mm | +76 mm |
| Oct | 11.2 °C | -0.5 °C | 112 mm | -16 mm |
| Nov | 6.6 °C | +1.3 °C | 129 mm | -9 mm |
| Dec | 3.9 °C | +2.6 °C | 33 mm | -94 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Arth?
Arth has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 6.7 °C and it receives 1,825 mm of precipitation per year.
What is the hottest day ever recorded in Arth?
The hottest day measured in Arth between 1940 and 2025 was 7 July 2015, reaching 31.1 °C.
What is the coldest day in Arth?
The coldest day measured in Arth between 1940 and 2025 was 12 January 1987, at -23.0 °C.
Does it snow in Arth?
Yes. Arth gets on average 343.4 cm of snow per year and has around 129 frost days.
Has the climate of Arth warmed?
Yes: Arth warmed by +2.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Arth?
The wettest day measured in Arth between 1940 and 2025 was 28 July 2019, with 85 mm of rain in 24 hours.
What was the windiest day in Arth?
The windiest day measured in Arth between 1940 and 2025 was 21 October 2014, with winds reaching 22.9 km/h.
What is the warmest month in Arth?
The warmest month in Arth is July (15.7 °C on average); the coldest is January (-2.1 °C).
How much does it rain in Arth?
Arth receives on average 1,825 mm of precipitation per year, spread over about 190 rainy days.
Is it sunny in Arth?
Arth gets on average 8.7 hours of sunshine per day, roughly 3,175 hours per year over 1940-2025.
What is the biggest single-day snowfall in Arth?
The heaviest 24-hour snowfall measured in Arth between 1940 and 2025 was 4 April 2019, with 31.0 cm.
Are there tropical nights in Arth?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Arth.
What was the most extreme apparent temperature in Arth?
In Arth, between 1940 and 2025, the highest apparent temperature reached 34.2 °C on 5 July 2015, and the lowest was -27.4 °C on 12 January 1987.
Compare Arth with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Arth