Click on a day for an hourly weather forecast
The temperatures in Thonon Les Bains in September are usually low and can range between 11°C and 20°C.
You can expect about 3 to 8 days of rain in Thonon Les Bains 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 Thonon Les Bains in September 2026.
If you’re planning to visit Thonon Les Bains in the near future, we highly recommend that you review the 14 day weather forecast for Thonon Les Bains before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 5° / -1° | 9 | 14 | 9 | 152 mm | Awful | Thonon Les Bains in January |
| February | 6° / -1° | 9 | 11 | 8 | 122 mm | Awful | Thonon Les Bains in February |
| March | 9° / 1° | 7 | 19 | 4 | 119 mm | Awful | Thonon Les Bains in March |
| April | 13° / 4° | 7 | 22 | 1 | 112 mm | Bad | Thonon Les Bains in April |
| May | 15° / 6° | 11 | 20 | 0 | 191 mm | Ok | Thonon Les Bains in May |
| June | 20° / 11° | 10 | 20 | 0 | 185 mm | Ok | Thonon Les Bains in June |
| July | 23° / 13° | 10 | 21 | 0 | 173 mm | Good | Thonon Les Bains in July |
| August | 24° / 14° | 8 | 23 | 0 | 144 mm | Good | Thonon Les Bains in August |
| September | 20° / 11° | 5 | 25 | 0 | 106 mm | Good | Thonon Les Bains in September |
| October | 16° / 7° | 5 | 25 | 0 | 109 mm | Good | Thonon Les Bains in October |
| November | 11° / 4° | 7 | 20 | 3 | 139 mm | Awful | Thonon Les Bains in November |
| December | 6° / 1° | 10 | 14 | 7 | 197 mm | Awful | Thonon Les Bains in December |