Bonn climate
Bonn is warmest in July, with average highs of 23 °C, and coldest in February, when nights average 0.6 °C. August is the wettest month (78 mm) and April the driest (49 mm). Figures are 1991–2020 climate normals.
Across a full year Bonn averages 781 mm of rain, 31 days above 25 °C and 50 days below freezing.
Germany · population 330,579 · 1991–2020 normals
Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month
- Warmest month July 23 °C
- Coldest month February 0.6 °C
- Driest month April 49 mm
- Wettest month August 78 mm
- Least cloud August 59 % cloud
- Hottest on record July 39 °C
- Coldest on record January -21 °C
What to expectBonn through the year
Bonn has a clear annual cycle: average daily highs run from 6.6 °C in February to 23 °C in July, a swing of 16 °C in mean temperature across the year.
Counted across a normal year, 31 days a year reach 25 °C, 6 of them reach 30 °C, 50 nights drop below freezing. The warmest reading in the 1991–2020 record is 39 °C, in July.
Rain is spread fairly evenly through the year, from 49 mm in April to 78 mm in August. There is no dry season to aim for.
Month by month
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| January | 5.4 °C | 63 mm | 73 % |
| February | 6.6 °C | 56 mm | 70 % |
| March | 10.3 °C | 60 mm | 67 % |
| April | 14.5 °C | 49 mm | 62 % |
| May | 18.3 °C | 62 mm | 65 % |
| June | 21.3 °C | 70 mm | 63 % |
| July | 23.4 °C | 75 mm | 61 % |
| August | 23.3 °C | 78 mm | 59 % |
| September | 19.3 °C | 64 mm | 62 % |
| October | 14.5 °C | 65 mm | 69 % |
| November | 9.3 °C | 67 mm | 75 % |
| December | 6.0 °C | 75 mm | 76 % |
Temperature month by month
| Month | Avg high | Avg low | Mean | Record high | Record low | Days above 25 °C | Days above 30 °C | Days below 0 °C |
|---|---|---|---|---|---|---|---|---|
| January | 5.4 °C | 0.7 °C | 3.0 °C | 14.6 °C | -20.8 °C | 0 | 0 | 13 |
| February | 6.6 °C | 0.6 °C | 3.4 °C | 19.4 °C | -13.4 °C | 0 | 0 | 12 |
| March | 10.3 °C | 2.4 °C | 6.3 °C | 21.7 °C | -11.9 °C | 0 | 0 | 8 |
| April | 14.5 °C | 5.2 °C | 10.0 °C | 26.5 °C | -4.3 °C | 0 | 0 | 2 |
| May | 18.3 °C | 9.1 °C | 14.0 °C | 31.9 °C | 1.1 °C | 2 | 0 | 0 |
| June | 21.3 °C | 12.4 °C | 17.1 °C | 34.8 °C | 3.1 °C | 6 | 1 | 0 |
| July | 23.4 °C | 14.6 °C | 19.2 °C | 38.6 °C | 7.6 °C | 11 | 2 | 0 |
| August | 23.3 °C | 14.4 °C | 18.9 °C | 37.0 °C | 7.2 °C | 9 | 2 | 0 |
| September | 19.3 °C | 11.4 °C | 15.3 °C | 33.1 °C | 3.5 °C | 3 | 0 | 0 |
| October | 14.5 °C | 8.2 °C | 11.2 °C | 26.0 °C | -2.9 °C | 0 | 0 | 0 |
| November | 9.3 °C | 4.4 °C | 6.8 °C | 20.5 °C | -6.7 °C | 0 | 0 | 4 |
| December | 6.0 °C | 1.6 °C | 3.8 °C | 15.0 °C | -15.5 °C | 0 | 0 | 11 |
Rain, sun and wind month by month
| Month | Rainfall | Wet days | Daylight | Cloud cover | Humidity | Wind |
|---|---|---|---|---|---|---|
| January | 63 mm | 13 | 8.5 h/day | 73 % | 83 % | 20 km/h |
| February | 56 mm | 11 | 10 h/day | 70 % | 80 % | 19 km/h |
| March | 60 mm | 13 | 12 h/day | 67 % | 77 % | 19 km/h |
| April | 49 mm | 10 | 14 h/day | 62 % | 72 % | 16 km/h |
| May | 62 mm | 12 | 16 h/day | 65 % | 72 % | 16 km/h |
| June | 70 mm | 12 | 16 h/day | 63 % | 72 % | 16 km/h |
| July | 75 mm | 13 | 16 h/day | 61 % | 71 % | 15 km/h |
| August | 78 mm | 11 | 15 h/day | 59 % | 72 % | 15 km/h |
| September | 64 mm | 10 | 13 h/day | 62 % | 77 % | 16 km/h |
| October | 65 mm | 12 | 11 h/day | 69 % | 81 % | 18 km/h |
| November | 67 mm | 13 | 9.0 h/day | 75 % | 85 % | 18 km/h |
| December | 75 mm | 14 | 8.0 h/day | 76 % | 85 % | 19 km/h |
How Bonn compares
The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.
| Destination | Summer high | Winter low | Rain per year | Days above 25 °C |
|---|---|---|---|---|
| Bonn | 23 °C | 0.6 °C | 781 mm | 31 |
| Köln · Germany | 23 °C | 0.4 °C | 911 mm | 29 |
| Solingen · Germany | 22 °C | -0.2 °C | 1,048 mm | 21 |
| Wuppertal · Germany | 22 °C | 0.06 °C | 1,097 mm | 22 |
| Düsseldorf · Germany | 23 °C | 0.5 °C | 885 mm | 29 |
Planning a trip? See the best time to visit Bonn.
QuestionsCommon questions about Bonn’s climate
When is the best time to visit Bonn?
That depends on what you want, so the honest answer is a comparison rather than a single month. June, July, August sit closest to 20 °C on average, July is the warmest month and April the driest. The month-by-month table above has the full picture.
How hot does Bonn get?
In July, the warmest month, daily highs average 23 °C. About 6 days a year pass 30 °C. The highest value in the 1991–2020 record is 39 °C.
How cold does it get in winter?
Nights average 0.6 °C in February, the coldest month. A normal year has 50 nights below freezing.
Which month is wettest in Bonn?
August, averaging 78 mm over 11 days with rain. The driest month is April with 49 mm. The year as a whole averages 781 mm.
Are these figures a forecast?
No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Bonn rather than what any particular week will bring. Individual years can differ substantially from the normal.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.