Grou climate — normals and trends
Grou (The Netherlands) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.7 °C and it receives 815 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 August (17.0 °C on average) and the coldest is January (2.7 °C). Rainfall peaks in July.
Grou averages 37 frost days, 0 hot days (≥ 30 °C) and 153 rainy days per year.
Grou has warmed by +1.9 °C between 1940 and 2025, or +0.22 °C per decade. This trend is statistically significant.
The number of frost days there went from about 51 to 23 per year over the period.
The hottest day of the period reached 33.6 °C (on 25 July 2019) and the coldest -18.0 °C (on 14 February 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
GrouFriesland
- coords
- 53.09°, 5.84°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.7°C
Average daily high
12.0°C
Average daily low
7.3°C
Annual rainfall
815mm
Sunshine / day
7.8h
Mean relative humidity
82%
Average peak wind
25.4km/h
Seasonal range
14.3°C
Frost days (< 0 °C)
37 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
153 d/yr
Annual snowfall
18.0 cm
Average feels-like high
9.1 °C
Average feels-like low
3.7 °C
Average peak gust
42.1 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
10.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.9 °C
since 1940
+0.2 °C per decade · r² = 0.41 · 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
33.6 °C
25 July 2019
Coldest day
-18.0 °C
14 February 1940
Wettest day
50 mm
15 September 1994
Windiest day
76.8 km/h
13 November 1972
Strongest gust
139.7 km/h
25 January 1990
Hottest feels-like
37.4 °C
25 July 2019
Coldest feels-like
-23.5 °C
14 January 1987
Snowiest day
15.6 cm
25 February 1958
Sunniest day
16.2 h
19 June 2005
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 | 5.5 °C | +1.2 °C | 60 mm | -3 mm |
| Feb | 5.5 °C | +0.8 °C | 31 mm | -19 mm |
| Mar | 10.8 °C | +3.2 °C | 12 mm | -41 mm |
| Apr | 14.1 °C | +3.1 °C | 33 mm | -16 mm |
| May | 16.3 °C | +1.4 °C | 42 mm | -19 mm |
| Jun | 20.2 °C | +2.5 °C | 92 mm | +26 mm |
| Jul | 21.4 °C | +1.9 °C | 94 mm | +8 mm |
| Aug | 21.3 °C | +1.5 °C | 41 mm | -45 mm |
| Sep | 18.3 °C | +1.0 °C | 86 mm | +9 mm |
| Oct | 13.7 °C | +0.4 °C | 122 mm | +47 mm |
| Nov | 9.5 °C | +0.8 °C | 91 mm | +15 mm |
| Dec | 7.7 °C | +1.9 °C | 29 mm | -43 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 Grou?
Grou has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.7 °C and it receives 815 mm of precipitation per year.
What is the hottest day ever recorded in Grou?
The hottest day measured in Grou between 1940 and 2025 was 25 July 2019, reaching 33.6 °C.
What is the coldest day in Grou?
The coldest day measured in Grou between 1940 and 2025 was 14 February 1940, at -18.0 °C.
Does it snow in Grou?
Yes. Grou gets on average 18.0 cm of snow per year and has around 37 frost days.
Has the climate of Grou warmed?
Yes: Grou warmed by +1.9 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Grou?
The wettest day measured in Grou between 1940 and 2025 was 15 September 1994, with 50 mm of rain in 24 hours.
What was the windiest day in Grou?
The windiest day measured in Grou between 1940 and 2025 was 13 November 1972, with winds reaching 76.8 km/h.
What is the warmest month in Grou?
The warmest month in Grou is August (17.0 °C on average); the coldest is January (2.7 °C).
How much does it rain in Grou?
Grou receives on average 815 mm of precipitation per year, spread over about 153 rainy days.
Is it sunny in Grou?
Grou gets on average 7.8 hours of sunshine per day, roughly 2,847 hours per year over 1940-2025.
What is the biggest single-day snowfall in Grou?
The heaviest 24-hour snowfall measured in Grou between 1940 and 2025 was 25 February 1958, with 15.6 cm.
Are there tropical nights in Grou?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Grou.
What was the most extreme apparent temperature in Grou?
In Grou, between 1940 and 2025, the highest apparent temperature reached 37.4 °C on 25 July 2019, and the lowest was -23.5 °C on 14 January 1987.
Compare Grou with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Grou