Click on a day for an hourly weather forecast
The temperatures in Iserlohn 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 Iserlohn 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 Iserlohn in September 2026.
If you’re planning to visit Iserlohn in the near future, we highly recommend that you review the 14 day weather forecast for Iserlohn before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 3° / -1° | 9 | 7 | 16 | 123 mm | Awful | Iserlohn in January |
| February | 5° / -1° | 8 | 8 | 13 | 90 mm | Awful | Iserlohn in February |
| March | 9° / 2° | 8 | 15 | 9 | 85 mm | Awful | Iserlohn in March |
| April | 13° / 5° | 6 | 21 | 3 | 64 mm | Bad | Iserlohn in April |
| May | 16° / 8° | 7 | 23 | 1 | 98 mm | Ok | Iserlohn in May |
| June | 20° / 11° | 7 | 23 | 0 | 109 mm | Ok | Iserlohn in June |
| July | 22° / 13° | 8 | 23 | 0 | 135 mm | Ok | Iserlohn in July |
| August | 22° / 14° | 6 | 25 | 0 | 111 mm | Good | Iserlohn in August |
| September | 19° / 11° | 5 | 25 | 0 | 75 mm | Good | Iserlohn in September |
| October | 13° / 7° | 7 | 23 | 1 | 85 mm | Bad | Iserlohn in October |
| November | 8° / 3° | 8 | 17 | 5 | 93 mm | Awful | Iserlohn in November |
| December | 4° / 0° | 10 | 10 | 12 | 128 mm | Awful | Iserlohn in December |