Olmen climate — normals and trends
Olmen has a temperate oceanic climate, averaging 10.3 °C annually with 777 mm of rain per year.
Climate normals · ERA5
OlmenFlanders
- coords
- 51.14°, 5.15°
- period
- 1940–2025 · 86 yrs
The normals for this period
The average of every indicator across the whole window: temperature, water, sky, wind and notable days.
Mean daily temperature
10.3°C
Average daily high
13.7°C
Average daily low
6.8°C
Annual rainfall
777mm
Sunshine / day
7.6h
Mean relative humidity
79%
Average peak wind
18.2km/h
Seasonal range
15.5°C
Frost days (< 0 °C)
50 d/yr
Hot days (≥ 30 °C)
4 d/yr
Rainy days (≥ 1 mm)
148 d/yr
Annual snowfall
18.8 cm
Average feels-like high
11.3 °C
Average feels-like low
4.0 °C
Average peak gust
37.8 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
10.5 MJ/m²
Has the climate changed?
What the yearly averages say about warming here, and whether the slope is statistically solid.
+2.0 °C
since 1940
+0.2 °C per decade · r² = 0.46 · 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).
Climate month by month
How an average year unfolds: when it rains, when it turns hot, when the sun is out.
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
The most extreme days ever measured here, then the year-by-year detail.
Hottest day
41.0 °C
25 July 2019
Coldest day
-23.3 °C
27 January 1942
Wettest day
39 mm
6 September 1962
Windiest day
55.9 km/h
25 January 1990
Strongest gust
128.2 km/h
18 January 2007
Hottest feels-like
42.0 °C
25 July 2019
Coldest feels-like
-28.8 °C
27 January 1942
Snowiest day
14.8 cm
27 December 2014
Sunniest day
15.8 h
2 July 2018
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and compare it with the normal: warmer, drier, more extreme?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 5.3 °C | +0.6 °C | 138 mm | +73 mm |
| Feb | 7.0 °C | +1.1 °C | 36 mm | -21 mm |
| Mar | 13.2 °C | +3.6 °C | 12 mm | -48 mm |
| Apr | 17.4 °C | +3.9 °C | 40 mm | -14 mm |
| May | 20.4 °C | +2.7 °C | 42 mm | -27 mm |
| Jun | 24.4 °C | +3.8 °C | 61 mm | -10 mm |
| Jul | 24.6 °C | +2.4 °C | 74 mm | -2 mm |
| Aug | 24.9 °C | +2.9 °C | 31 mm | -39 mm |
| Sep | 20.0 °C | +1.1 °C | 82 mm | +21 mm |
| Oct | 14.5 °C | +0.2 °C | 82 mm | +20 mm |
| Nov | 10.4 °C | +1.5 °C | 60 mm | -6 mm |
| Dec | 8.3 °C | +2.5 °C | 30 mm | -38 mm |
The year's extremes
What was the weather like that day?
The weather actually measured on a given date, anywhere in the covered window.
Olmen (Belgium) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 10.3 °C and it receives 777 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 (18.1 °C on average) and the coldest is January (2.6 °C). Rainfall peaks in July.
Olmen averages 50 frost days, 4 hot days (≥ 30 °C) and 148 rainy days per year.
Olmen 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 65 to 35 per year over the period.
The hottest day of the period reached 41.0 °C (on 25 July 2019) and the coldest -23.3 °C (on 27 January 1942).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Frequently asked questions
What is the climate of Olmen?
Olmen has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 10.3 °C and it receives 777 mm of precipitation per year.
What is the hottest day ever recorded in Olmen?
The hottest day measured in Olmen between 1940 and 2025 was 25 July 2019, reaching 41.0 °C.
What is the coldest day in Olmen?
The coldest day measured in Olmen between 1940 and 2025 was 27 January 1942, at -23.3 °C.
Does it snow in Olmen?
Yes. Olmen gets on average 18.8 cm of snow per year and has around 50 frost days.
Has the climate of Olmen warmed?
Yes: Olmen warmed by +2.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Olmen?
The wettest day measured in Olmen between 1940 and 2025 was 6 September 1962, with 39 mm of rain in 24 hours.
What was the windiest day in Olmen?
The windiest day measured in Olmen between 1940 and 2025 was 25 January 1990, with winds reaching 55.9 km/h.
What is the warmest month in Olmen?
The warmest month in Olmen is July (18.1 °C on average); the coldest is January (2.6 °C).
How much does it rain in Olmen?
Olmen receives on average 777 mm of precipitation per year, spread over about 148 rainy days.
Is it sunny in Olmen?
Olmen gets on average 7.6 hours of sunshine per day, roughly 2,774 hours per year over 1940-2025.
What is the biggest single-day snowfall in Olmen?
The heaviest 24-hour snowfall measured in Olmen between 1940 and 2025 was 27 December 2014, with 14.8 cm.
Are there tropical nights in Olmen?
Yes: Olmen has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Olmen?
In Olmen, between 1940 and 2025, the highest apparent temperature reached 42.0 °C on 25 July 2019, and the lowest was -28.8 °C on 27 January 1942.
These forecasts and records come from our own weather API. Developer documentation →
Compare Olmen with another city
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Nearby cities
The climate around Olmen