Ilmajoki climate — normals and trends
Ilmajoki (Finland) has a subarctic climate (Dfc) under the Köppen-Geiger classification. Its mean annual temperature is 4.0 °C and it receives 585 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 (16.4 °C on average) and the coldest is January (-7.2 °C). Rainfall peaks in August.
Ilmajoki averages 168 frost days, 0 hot days (≥ 30 °C) and 122 rainy days per year.
Ilmajoki has warmed by +2.0 °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 181 to 155 per year over the period.
The hottest day of the period reached 32.0 °C (on 29 July 2010) and the coldest -39.6 °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
IlmajokiSouth Ostrobothnia
- coords
- 62.73°, 22.57°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
4.0°C
Average daily high
7.5°C
Average daily low
0.3°C
Annual rainfall
585mm
Sunshine / day
7.2h
Mean relative humidity
80%
Average peak wind
16.3km/h
Seasonal range
23.6°C
Frost days (< 0 °C)
168 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
122 d/yr
Annual snowfall
109.3 cm
Average feels-like high
4.2 °C
Average feels-like low
-3.3 °C
Average peak gust
36.5 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
8.9 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.0 °C
since 1940
+0.2 °C per decade · r² = 0.26 · 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
-39.6 °C
7 January 1987
Wettest day
82 mm
6 August 1967
Windiest day
40.7 km/h
27 May 1986
Strongest gust
102.2 km/h
14 January 1984
Hottest feels-like
33.1 °C
15 July 2003
Coldest feels-like
-44.5 °C
7 January 1987
Snowiest day
14.3 cm
8 April 1982
Sunniest day
19.0 h
16 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 | -1.3 °C | +3.3 °C | 43 mm | +10 mm |
| Feb | -0.3 °C | +3.9 °C | 11 mm | -16 mm |
| Mar | 5.2 °C | +4.5 °C | 26 mm | -3 mm |
| Apr | 9.5 °C | +2.4 °C | 34 mm | -3 mm |
| May | 12.4 °C | -1.4 °C | 45 mm | -1 mm |
| Jun | 17.2 °C | -1.1 °C | 79 mm | +17 mm |
| Jul | 24.4 °C | +3.8 °C | 78 mm | +3 mm |
| Aug | 18.6 °C | -0.3 °C | 97 mm | +18 mm |
| Sep | 16.8 °C | +3.4 °C | 66 mm | +7 mm |
| Oct | 8.7 °C | +1.9 °C | 52 mm | +2 mm |
| Nov | 3.5 °C | +2.4 °C | 51 mm | +4 mm |
| Dec | 2.4 °C | +4.7 °C | 67 mm | +26 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 Ilmajoki?
Ilmajoki has a subarctic climate (Köppen Dfc). Over 1940-2025, the average annual temperature is 4.0 °C and it receives 585 mm of precipitation per year.
What is the hottest day ever recorded in Ilmajoki?
The hottest day measured in Ilmajoki between 1940 and 2025 was 29 July 2010, reaching 32.0 °C.
What is the coldest day in Ilmajoki?
The coldest day measured in Ilmajoki between 1940 and 2025 was 7 January 1987, at -39.6 °C.
Does it snow in Ilmajoki?
Yes. Ilmajoki gets on average 109.3 cm of snow per year and has around 168 frost days.
Has the climate of Ilmajoki warmed?
Yes: Ilmajoki warmed by +2.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Ilmajoki?
The wettest day measured in Ilmajoki between 1940 and 2025 was 6 August 1967, with 82 mm of rain in 24 hours.
What was the windiest day in Ilmajoki?
The windiest day measured in Ilmajoki between 1940 and 2025 was 27 May 1986, with winds reaching 40.7 km/h.
What is the warmest month in Ilmajoki?
The warmest month in Ilmajoki is July (16.4 °C on average); the coldest is January (-7.2 °C).
How much does it rain in Ilmajoki?
Ilmajoki receives on average 585 mm of precipitation per year, spread over about 122 rainy days.
Is it sunny in Ilmajoki?
Ilmajoki gets on average 7.2 hours of sunshine per day, roughly 2,628 hours per year over 1940-2025.
What is the biggest single-day snowfall in Ilmajoki?
The heaviest 24-hour snowfall measured in Ilmajoki between 1940 and 2025 was 8 April 1982, with 14.3 cm.
Are there tropical nights in Ilmajoki?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Ilmajoki.
What was the most extreme apparent temperature in Ilmajoki?
In Ilmajoki, between 1940 and 2025, the highest apparent temperature reached 33.1 °C on 15 July 2003, and the lowest was -44.5 °C on 7 January 1987.
Compare Ilmajoki with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Ilmajoki