Click on a day for an hourly weather forecast
The temperatures in Solothurn in September are quite cold with temperatures between 7°C and 20°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Solothurn 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 Solothurn in September 2026.
If you’re planning to visit Solothurn in the near future, we highly recommend that you review the 14 day weather forecast for Solothurn before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 4° / -5° | 7 | 12 | 12 | 85 mm | Awful | Solothurn in January |
| February | 5° / -5° | 7 | 10 | 12 | 64 mm | Awful | Solothurn in February |
| March | 10° / -1° | 6 | 17 | 8 | 67 mm | Bad | Solothurn in March |
| April | 14° / 2° | 6 | 21 | 3 | 73 mm | Ok | Solothurn in April |
| May | 18° / 4° | 10 | 21 | 0 | 135 mm | Ok | Solothurn in May |
| June | 22° / 8° | 9 | 21 | 0 | 124 mm | Ok | Solothurn in June |
| July | 24° / 10° | 7 | 24 | 0 | 116 mm | Good | Solothurn in July |
| August | 24° / 10° | 7 | 24 | 0 | 96 mm | Good | Solothurn in August |
| September | 20° / 7° | 4 | 26 | 0 | 68 mm | Good | Solothurn in September |
| October | 15° / 3° | 5 | 26 | 1 | 76 mm | Good | Solothurn in October |
| November | 10° / 0° | 6 | 18 | 6 | 74 mm | Bad | Solothurn in November |
| December | 5° / -3° | 7 | 15 | 9 | 96 mm | Awful | Solothurn in December |