Jalasjärvi climate — normals and trends
Jalasjärvi (Finland) has a subarctic climate (Dfc) under the Köppen-Geiger classification. Its mean annual temperature is 3.8 °C and it receives 609 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 (16.3 °C on average) and the coldest is January (-7.6 °C). Rainfall peaks in July.
Jalasjärvi averages 171 frost days, 0 hot days (≥ 30 °C) and 126 rainy days per year.
Jalasjärvi has warmed by +2.1 °C between 1940 and 2025, or +0.24 °C per decade. This trend is statistically significant.
The number of frost days there went from about 184 to 158 per year over the period.
The hottest day of the period reached 32.0 °C (on 29 July 2010) and the coldest -39.1 °C (on 7 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
JalasjärviSouth Ostrobothnia
- coords
- 62.49°, 22.76°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
3.8°C
Average daily high
7.3°C
Average daily low
0.1°C
Annual rainfall
609mm
Sunshine / day
7.1h
Mean relative humidity
80%
Average peak wind
15.9km/h
Seasonal range
23.9°C
Frost days (< 0 °C)
171 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
126 d/yr
Annual snowfall
118.2 cm
Average feels-like high
4.0 °C
Average feels-like low
-3.5 °C
Average peak gust
35.5 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
8.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.1 °C
since 1940
+0.2 °C per decade · r² = 0.28 · 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
32.0 °C
29 July 2010
Coldest day
-39.1 °C
7 January 1987
Wettest day
63 mm
6 August 1967
Windiest day
40.7 km/h
27 May 1986
Strongest gust
101.5 km/h
14 January 1984
Hottest feels-like
32.9 °C
29 July 2010
Coldest feels-like
-44.4 °C
7 January 1987
Snowiest day
15.8 cm
13 November 1996
Sunniest day
19.0 h
23 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 | -1.2 °C | +3.8 °C | 44 mm | +9 mm |
| Feb | -0.3 °C | +4.2 °C | 11 mm | -17 mm |
| Mar | 4.9 °C | +4.5 °C | 29 mm | -1 mm |
| Apr | 9.4 °C | +2.5 °C | 41 mm | +3 mm |
| May | 12.4 °C | -1.5 °C | 52 mm | +5 mm |
| Jun | 17.2 °C | -1.2 °C | 82 mm | +17 mm |
| Jul | 24.5 °C | +3.9 °C | 73 mm | -10 mm |
| Aug | 18.3 °C | -0.4 °C | 90 mm | +8 mm |
| Sep | 16.5 °C | +3.3 °C | 70 mm | +10 mm |
| Oct | 8.3 °C | +1.8 °C | 55 mm | +4 mm |
| Nov | 3.5 °C | +2.7 °C | 48 mm | +0 mm |
| Dec | 2.2 °C | +4.9 °C | 65 mm | +22 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 Jalasjärvi?
Jalasjärvi has a subarctic climate (Köppen Dfc). Over 1940-2025, the average annual temperature is 3.8 °C and it receives 609 mm of precipitation per year.
What is the hottest day ever recorded in Jalasjärvi?
The hottest day measured in Jalasjärvi between 1940 and 2025 was 29 July 2010, reaching 32.0 °C.
What is the coldest day in Jalasjärvi?
The coldest day measured in Jalasjärvi between 1940 and 2025 was 7 January 1987, at -39.1 °C.
Does it snow in Jalasjärvi?
Yes. Jalasjärvi gets on average 118.2 cm of snow per year and has around 171 frost days.
Has the climate of Jalasjärvi warmed?
Yes: Jalasjärvi warmed by +2.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Jalasjärvi?
The wettest day measured in Jalasjärvi between 1940 and 2025 was 6 August 1967, with 63 mm of rain in 24 hours.
What was the windiest day in Jalasjärvi?
The windiest day measured in Jalasjärvi between 1940 and 2025 was 27 May 1986, with winds reaching 40.7 km/h.
What is the warmest month in Jalasjärvi?
The warmest month in Jalasjärvi is July (16.3 °C on average); the coldest is January (-7.6 °C).
How much does it rain in Jalasjärvi?
Jalasjärvi receives on average 609 mm of precipitation per year, spread over about 126 rainy days.
Is it sunny in Jalasjärvi?
Jalasjärvi gets on average 7.1 hours of sunshine per day, roughly 2,592 hours per year over 1940-2025.
What is the biggest single-day snowfall in Jalasjärvi?
The heaviest 24-hour snowfall measured in Jalasjärvi between 1940 and 2025 was 13 November 1996, with 15.8 cm.
Are there tropical nights in Jalasjärvi?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Jalasjärvi.
What was the most extreme apparent temperature in Jalasjärvi?
In Jalasjärvi, between 1940 and 2025, the highest apparent temperature reached 32.9 °C on 29 July 2010, and the lowest was -44.4 °C on 7 January 1987.
Compare Jalasjärvi with another city
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Nearby cities
The climate around Jalasjärvi