Aosta climate — normals and trends
Aosta (Italy) has a subarctic climate (Dfc) under the Köppen-Geiger classification. Its mean annual temperature is 0.4 °C and it receives 1,168 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 (10.9 °C on average) and the coldest is January (-9.7 °C). Rainfall peaks in November.
Aosta averages 230 frost days, 0 hot days (≥ 30 °C) and 165 rainy days per year.
Aosta has warmed by +2.7 °C between 1940 and 2025, or +0.32 °C per decade. This trend is statistically significant.
The number of frost days there went from about 254 to 206 per year over the period.
The hottest day of the period reached 26.2 °C (on 23 August 2023) and the coldest -32.1 °C (on 21 January 1940).
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
AostaAosta Valley
- coords
- 45.74°, 7.32°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
0.4°C
Average daily high
4.3°C
Average daily low
-3.6°C
Annual rainfall
1,168mm
Sunshine / day
9.5h
Mean relative humidity
75%
Average peak wind
5.9km/h
Seasonal range
20.6°C
Frost days (< 0 °C)
230 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
165 d/yr
Annual snowfall
515.9 cm
Average feels-like high
1.9 °C
Average feels-like low
-6.6 °C
Average peak gust
39.0 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
14.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.7 °C
since 1940
+0.3 °C per decade · r² = 0.62 · 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
26.2 °C
23 August 2023
Coldest day
-32.1 °C
21 January 1940
Wettest day
99 mm
27 September 1942
Windiest day
16.7 km/h
27 February 1990
Strongest gust
167.0 km/h
27 February 1990
Hottest feels-like
25.9 °C
29 June 2025
Coldest feels-like
-37.1 °C
21 January 1940
Snowiest day
55.9 cm
21 March 1971
Sunniest day
15.0 h
25 May 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 | -3.0 °C | +3.7 °C | 139 mm | +44 mm |
| Feb | -0.8 °C | +3.5 °C | 29 mm | -61 mm |
| Mar | 1.1 °C | +1.8 °C | 65 mm | -30 mm |
| Apr | 5.3 °C | +2.7 °C | 188 mm | +89 mm |
| May | 9.2 °C | +2.3 °C | 112 mm | +7 mm |
| Jun | 18.3 °C | +6.2 °C | 91 mm | -5 mm |
| Jul | 15.8 °C | 0.0 °C | 98 mm | +6 mm |
| Aug | 17.8 °C | +2.4 °C | 87 mm | -7 mm |
| Sep | 11.6 °C | -0.3 °C | 127 mm | +43 mm |
| Oct | 7.0 °C | +0.7 °C | 123 mm | +24 mm |
| Nov | 0.3 °C | +1.5 °C | 82 mm | -32 mm |
| Dec | -2.0 °C | +4.0 °C | 51 mm | -55 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 Aosta?
Aosta has a subarctic climate (Köppen Dfc). Over 1940-2025, the average annual temperature is 0.4 °C and it receives 1,168 mm of precipitation per year.
What is the hottest day ever recorded in Aosta?
The hottest day measured in Aosta between 1940 and 2025 was 23 August 2023, reaching 26.2 °C.
What is the coldest day in Aosta?
The coldest day measured in Aosta between 1940 and 2025 was 21 January 1940, at -32.1 °C.
Does it snow in Aosta?
Yes. Aosta gets on average 515.9 cm of snow per year and has around 230 frost days.
Has the climate of Aosta warmed?
Yes: Aosta warmed by +2.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Aosta?
The wettest day measured in Aosta between 1940 and 2025 was 27 September 1942, with 99 mm of rain in 24 hours.
What was the windiest day in Aosta?
The windiest day measured in Aosta between 1940 and 2025 was 27 February 1990, with winds reaching 16.7 km/h.
What is the warmest month in Aosta?
The warmest month in Aosta is July (10.9 °C on average); the coldest is January (-9.7 °C).
How much does it rain in Aosta?
Aosta receives on average 1,168 mm of precipitation per year, spread over about 165 rainy days.
Is it sunny in Aosta?
Aosta gets on average 9.5 hours of sunshine per day, roughly 3,468 hours per year over 1940-2025.
What is the biggest single-day snowfall in Aosta?
The heaviest 24-hour snowfall measured in Aosta between 1940 and 2025 was 21 March 1971, with 55.9 cm.
Are there tropical nights in Aosta?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Aosta.
What was the most extreme apparent temperature in Aosta?
In Aosta, between 1940 and 2025, the highest apparent temperature reached 25.9 °C on 29 June 2025, and the lowest was -37.1 °C on 21 January 1940.
Compare Aosta with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Aosta