Alta climate — normals and trends
Alta (Norway) has a subarctic climate (Dfc) under the Köppen-Geiger classification. Its mean annual temperature is -1.0 °C and it receives 637 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 (12.4 °C on average) and the coldest is January (-12.1 °C). Rainfall peaks in July.
Alta averages 223 frost days, 0 hot days (≥ 30 °C) and 149 rainy days per year.
Alta has warmed by +3.7 °C between 1940 and 2025, or +0.43 °C per decade. This trend is statistically significant.
The number of frost days there went from about 246 to 200 per year over the period.
The hottest day of the period reached 29.8 °C (on 1 July 1972) and the coldest -40.1 °C (on 28 January 1999).
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
AltaFinnmark
- coords
- 69.97°, 23.27°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
-1.0°C
Average daily high
1.9°C
Average daily low
-4.2°C
Annual rainfall
637mm
Sunshine / day
6.2h
Mean relative humidity
81%
Average peak wind
13.2km/h
Seasonal range
24.5°C
Frost days (< 0 °C)
223 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
149 d/yr
Annual snowfall
221.0 cm
Average feels-like high
-1.6 °C
Average feels-like low
-8.0 °C
Average peak gust
33.8 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
7.2 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+3.7 °C
since 1940
+0.4 °C per decade · r² = 0.53 · 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
29.8 °C
1 July 1972
Coldest day
-40.1 °C
28 January 1999
Wettest day
47 mm
29 May 1979
Windiest day
47.0 km/h
1 February 1993
Strongest gust
141.1 km/h
1 February 1993
Hottest feels-like
30.6 °C
20 July 1988
Coldest feels-like
-45.5 °C
28 January 1999
Snowiest day
22.2 cm
17 January 1957
Sunniest day
23.6 h
5 June 1944
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 | -6.6 °C | +2.5 °C | 62 mm | +19 mm |
| Feb | -1.5 °C | +7.1 °C | 57 mm | +20 mm |
| Mar | -1.8 °C | +2.7 °C | 70 mm | +28 mm |
| Apr | 0.3 °C | -0.3 °C | 108 mm | +67 mm |
| May | 7.9 °C | +2.5 °C | 51 mm | +2 mm |
| Jun | 11.9 °C | +0.3 °C | 68 mm | -1 mm |
| Jul | 17.7 °C | +2.2 °C | 84 mm | +10 mm |
| Aug | 15.3 °C | +1.7 °C | 125 mm | +53 mm |
| Sep | 13.3 °C | +4.7 °C | 75 mm | +13 mm |
| Oct | 4.5 °C | +3.2 °C | 70 mm | +9 mm |
| Nov | -4.3 °C | +0.1 °C | 53 mm | +8 mm |
| Dec | -4.4 °C | +2.9 °C | 77 mm | +35 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 Alta?
Alta has a subarctic climate (Köppen Dfc). Over 1940-2025, the average annual temperature is -1.0 °C and it receives 637 mm of precipitation per year.
What is the hottest day ever recorded in Alta?
The hottest day measured in Alta between 1940 and 2025 was 1 July 1972, reaching 29.8 °C.
What is the coldest day in Alta?
The coldest day measured in Alta between 1940 and 2025 was 28 January 1999, at -40.1 °C.
Does it snow in Alta?
Yes. Alta gets on average 221.0 cm of snow per year and has around 223 frost days.
Has the climate of Alta warmed?
Yes: Alta warmed by +3.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Alta?
The wettest day measured in Alta between 1940 and 2025 was 29 May 1979, with 47 mm of rain in 24 hours.
What was the windiest day in Alta?
The windiest day measured in Alta between 1940 and 2025 was 1 February 1993, with winds reaching 47.0 km/h.
What is the warmest month in Alta?
The warmest month in Alta is July (12.4 °C on average); the coldest is January (-12.1 °C).
How much does it rain in Alta?
Alta receives on average 637 mm of precipitation per year, spread over about 149 rainy days.
Is it sunny in Alta?
Alta gets on average 6.2 hours of sunshine per day, roughly 2,263 hours per year over 1940-2025.
What is the biggest single-day snowfall in Alta?
The heaviest 24-hour snowfall measured in Alta between 1940 and 2025 was 17 January 1957, with 22.2 cm.
Are there tropical nights in Alta?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Alta.
What was the most extreme apparent temperature in Alta?
In Alta, between 1940 and 2025, the highest apparent temperature reached 30.6 °C on 20 July 1988, and the lowest was -45.5 °C on 28 January 1999.
Compare Alta with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Alta