Click on a day for an hourly weather forecast
The temperatures in Aachen in September are usually low and can range between 11°C and 19°C.
You can expect about 3 to 8 days of rain in Aachen during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Aachen in September 2025.
If you’re planning to visit Aachen in the near future, we highly recommend that you review the 14 day weather forecast for Aachen before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 4° / 1° | 9 | 13 | 9 | 86 mm | Awful | Aachen in January |
| February | 6° / 1° | 8 | 13 | 7 | 74 mm | Awful | Aachen in February |
| March | 10° / 3° | 7 | 21 | 3 | 71 mm | Awful | Aachen in March |
| April | 14° / 6° | 5 | 24 | 1 | 51 mm | Good | Aachen in April |
| May | 17° / 9° | 7 | 24 | 0 | 96 mm | Ok | Aachen in May |
| June | 21° / 12° | 6 | 24 | 0 | 102 mm | Good | Aachen in June |
| July | 23° / 14° | 6 | 25 | 0 | 93 mm | Perfect | Aachen in July |
| August | 23° / 14° | 5 | 26 | 0 | 89 mm | Perfect | Aachen in August |
| September | 19° / 11° | 4 | 26 | 0 | 63 mm | Good | Aachen in September |
| October | 14° / 8° | 6 | 25 | 0 | 66 mm | Good | Aachen in October |
| November | 9° / 5° | 8 | 20 | 2 | 71 mm | Awful | Aachen in November |
| December | 6° / 2° | 10 | 15 | 6 | 100 mm | Awful | Aachen in December |