Bonn Weather in September
Bonn in September averages 20°C (68°F) during the day and 11°C (52°F) at night. Keep in mind that quite a bit of rainfall is expected this month.
Rainfall in Bonn in September
This month experiences about 15 days of rain according to historical data, averaging 72 mm (2.8 in). Rain this month is fairly typical, a standard mix of wet and dry days with no particularly heavy or persistent showers.
Temperature in Bonn in September
September is one of the better months to visit Bonn. Expect 20°C (68°F) during the day and 11°C (52°F) at night. Conditions are often most pleasant around the middle of the day. With overnight lows of 11°C (52°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.
Sunshine in Bonn in September
The month brings about 142 hours of sunlight, offering a comfortable mix of sun and overcast.If your ideal day consists of dry skies and pleasant temperatures, June, July, August and September typically offer the best circumstances for Bonn.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Germany, check out our Bonn's climate page.
Bonn Temperature in September
Min Temperature
11°C (52°F)
Max Temperature
20°C (68°F)
Chance of Rain
48%
Precipitation
72 mm (2.8 in)
Rainy days
15 days
Sunshine
142 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Bonn typically drop from around 21°C (70°F) at the start of September to approximately 18°C (64°F) by the end. Nights are cool, with lows typically ranging from 9°C (48°F) to 12°C (54°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Bonn in September
Browse day-by-day weather records for Bonn spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Bonn historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Bonn.
- The hottest September day on record in Bonn reached 33°C (91°F) (September 6, 2013).
- On September 30, 1995, Bonn saw its coldest September day with temperatures maxing out at 10°C (50°F).
- The coldest night in September in Bonn was on September 29, 2002, with a minimum of 0°C (32°F).
Best Places in Germany in September
Find out more about the weather in Germany and which places have the best travel conditions in this month. See all of Germany in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Bonn in September
Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Wet weather is likely, so pack waterproof gear for multiple rainy days. Bring sunglasses since you'll have some sunny periods throughout the monthWhat To Do in Bonn in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Germany, check out our Bonn's climate page.
See the full Bonn climate overview or explore weather in Germany.
