Aachen climate — normals and trends
Aachen (Germany) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 9.4 °C and it receives 856 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 (17.3 °C on average) and the coldest is January (1.7 °C). Rainfall peaks in July.
Aachen averages 57 frost days, 3 hot days (≥ 30 °C) and 160 rainy days per year.
Aachen 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 73 to 41 per year over the period.
The hottest day of the period reached 39.7 °C (on 25 July 2019) and the coldest -20.9 °C (on 1 January 1979).
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
AachenNorth Rhine-Westphalia
- coords
- 50.78°, 6.08°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.4°C
Average daily high
12.7°C
Average daily low
6.3°C
Annual rainfall
856mm
Sunshine / day
7.5h
Mean relative humidity
80%
Average peak wind
19.4km/h
Seasonal range
15.6°C
Frost days (< 0 °C)
57 d/yr
Hot days (≥ 30 °C)
3 d/yr
Rainy days (≥ 1 mm)
160 d/yr
Annual snowfall
39.8 cm
Average feels-like high
10.1 °C
Average feels-like low
3.3 °C
Average peak gust
39.0 km/h
Tropical nights (≥ 20 °C)
1 d/yr
Solar radiation
10.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.1 °C
since 1940
+0.2 °C per decade · r² = 0.43 · 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
39.7 °C
25 July 2019
Coldest day
-20.9 °C
1 January 1979
Wettest day
77 mm
14 July 2021
Windiest day
57.5 km/h
18 January 2007
Strongest gust
132.1 km/h
24 November 1984
Hottest feels-like
40.0 °C
6 July 1957
Coldest feels-like
-25.9 °C
1 January 1979
Snowiest day
15.5 cm
1 February 1953
Sunniest day
15.5 h
30 June 2015
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 | 4.5 °C | +0.8 °C | 151 mm | +80 mm |
| Feb | 6.3 °C | +1.4 °C | 34 mm | -32 mm |
| Mar | 12.6 °C | +3.9 °C | 13 mm | -56 mm |
| Apr | 16.1 °C | +3.6 °C | 64 mm | +0 mm |
| May | 19.0 °C | +2.4 °C | 53 mm | -22 mm |
| Jun | 23.9 °C | +4.4 °C | 62 mm | -15 mm |
| Jul | 23.8 °C | +2.5 °C | 104 mm | +21 mm |
| Aug | 24.0 °C | +2.9 °C | 26 mm | -49 mm |
| Sep | 19.0 °C | +1.0 °C | 98 mm | +36 mm |
| Oct | 13.2 °C | -0.3 °C | 86 mm | +22 mm |
| Nov | 9.8 °C | +1.9 °C | 65 mm | -7 mm |
| Dec | 7.7 °C | +2.9 °C | 34 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 Aachen?
Aachen has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 9.4 °C and it receives 856 mm of precipitation per year.
What is the hottest day ever recorded in Aachen?
The hottest day measured in Aachen between 1940 and 2025 was 25 July 2019, reaching 39.7 °C.
What is the coldest day in Aachen?
The coldest day measured in Aachen between 1940 and 2025 was 1 January 1979, at -20.9 °C.
Does it snow in Aachen?
Yes. Aachen gets on average 39.8 cm of snow per year and has around 57 frost days.
Has the climate of Aachen warmed?
Yes: Aachen warmed by +2.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Aachen?
The wettest day measured in Aachen between 1940 and 2025 was 14 July 2021, with 77 mm of rain in 24 hours.
What was the windiest day in Aachen?
The windiest day measured in Aachen between 1940 and 2025 was 18 January 2007, with winds reaching 57.5 km/h.
What is the warmest month in Aachen?
The warmest month in Aachen is July (17.3 °C on average); the coldest is January (1.7 °C).
How much does it rain in Aachen?
Aachen receives on average 856 mm of precipitation per year, spread over about 160 rainy days.
Is it sunny in Aachen?
Aachen gets on average 7.5 hours of sunshine per day, roughly 2,738 hours per year over 1940-2025.
What is the biggest single-day snowfall in Aachen?
The heaviest 24-hour snowfall measured in Aachen between 1940 and 2025 was 1 February 1953, with 15.5 cm.
Are there tropical nights in Aachen?
Yes: Aachen has on average 1 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Aachen?
In Aachen, between 1940 and 2025, the highest apparent temperature reached 40.0 °C on 6 July 1957, and the lowest was -25.9 °C on 1 January 1979.
Compare Aachen with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Aachen