Bonn climate
Bonn (North Rhine-Westphalia, Germany) has a temperate oceanic climate (Köppen Cfb). The average temperature over the year is 11 °C51 °F, and about 771 mm30 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Bonn climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 540 | 031 | 236 | 632.5 |
| Feb | 642 | 031 | 337 | 552.2 |
| Mar | 1050 | 235 | 643 | 562.2 |
| Apr | 1559 | 541 | 1050 | 471.9 |
| May | 1966 | 948 | 1457 | 722.8 |
| Jun | 2373 | 1355 | 1864 | 753.0 |
| Jul | 2578 | 1558 | 2068 | 773.0 |
| Aug | 2577 | 1458 | 2067 | 803.1 |
| Sep | 2170 | 1051 | 1660 | 582.3 |
| Oct | 1559 | 745 | 1152 | 592.3 |
| Nov | 949 | 439 | 744 | 632.5 |
| Dec | 542 | 134 | 338 | 672.6 |
| Year | 2578 | 031 | 1151 | 77130 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 94% | 79% | 0.8 | 8:25 |
| Feb | 92% | 76% | 1.5 | 9:57 |
| Mar | 87% | 70% | 2.7 | 11:43 |
| Apr | 81% | 66% | 4.2 | 13:45 |
| May | 79% | 71% | 4.9 | 15:29 |
| Jun | 76% | 71% | 5.4 | 16:28 |
| Jul | 71% | 68% | 5.2 | 16:04 |
| Aug | 72% | 67% | 4.4 | 14:31 |
| Sep | 76% | 64% | 3.3 | 12:32 |
| Oct | 86% | 71% | 1.9 | 10:35 |
| Nov | 93% | 79% | 0.9 | 8:51 |
| Dec | 95% | 81% | 0.6 | 7:59 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Bonn is like
The warmest month is July, with an average high of 25 °C78 °F and a low of 15 °C58 °F. The coldest is January, when highs average 5 °C40 °F and lows 0 °C31 °F. There is a clear seasonal cycle, with 17.9 °C32.3 °F between the average temperature of the warmest and the coolest month.
Annual precipitation is moderate at about 771 mm30 in. Rain is spread fairly evenly through the year. The wettest month is August (80 mm3.1 in), the driest is April (47 mm1.9 in).
Relative humidity ranges from 71% in July to 95% in December. The clearest skies (lowest average cloud amount, 64%) are typical of September. Average wind speed near the ground ranges from 9 km/h (6 mph) in August to 14 km/h (9 mph) in January. Daylight lasts from about 8.0 hours in December to 16.5 hours in June.
Best time to visit Bonn
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May–September: average highs of 19 °C66 °F to 25 °C78 °F with 58 mm2.3 in to 80 mm3.1 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of 5 °C40 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Bonn
- Winter (December–February) — highs 540 to 6 °C42 °F, lows 031 to 1 °C34 °F, about 62 mm2.4 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1050 to 19 °C66 °F, lows 235 to 9 °C48 °F, about 58 mm2.3 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
- Summer (June–August) — highs 2373 to 25 °C78 °F, lows 1355 to 15 °C58 °F, about 77 mm3.0 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
- Autumn (September–November) — highs 949 to 21 °C70 °F, lows 439 to 10 °C51 °F, about 60 mm2.4 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
How Bonn compares
Compared with Köln, about 24 km to the northwest, Bonn has practically the same average temperature and receives a similar amount of precipitation.
Of the 62 places in Germany covered by World Climates, Bonn is the 4th warmest by annual mean temperature and the 24th wettest by annual precipitation. See all of them on the Germany climate page.
Places in other countries with the most similar temperature and rainfall pattern: Dijon (France, Cfb), Maastricht (The Netherlands, Cfb) and Nancy (France, Cfb).
Nearby places
- Köln 24 km · 11 °C51 °F · 791 mm31 in
- Bergisch Gladbach 28 km · 10 °C51 °F · 791 mm31 in
- Solingen 49 km · 9 °C49 °F · 791 mm31 in
- Remscheid 50 km · 9 °C47 °F · 905 mm36 in
- Koblenz 54 km · 11 °C51 °F · 785 mm31 in
- Düsseldorf 59 km · 11 °C51 °F · 791 mm31 in
- Siegen 67 km · 9 °C48 °F · 910 mm36 in
- Mönchengladbach 68 km · 11 °C51 °F · 747 mm29 in
Frequently asked questions
What is the warmest month in Bonn?
July is the warmest month in Bonn, with an average high of 25 °C (78 °F) and an average low of 15 °C (58 °F).
What is the coldest month in Bonn?
January is the coldest month, with an average high of 5 °C (40 °F) and an average low of 0 °C (31 °F).
When does it rain the most in Bonn?
August is the wettest month with about 80 mm (3.1 in) of precipitation; April is the driest with about 47 mm (1.9 in).
What is the best time to visit Bonn?
Judging by long-term averages, the most comfortable months are May–September.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 370 m, while Bonn lies at about 64 m. Temperatures on this page were therefore adjusted by +2 °C3.6 °F using the standard lapse rate of 6.5 °C per 1,000 m.