Click on a day for an hourly weather forecast
The temperatures in Butte in September are quite cold with temperatures between 5°C and 19°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Butte 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.
Please note that Butte can expect a few days of snow in September.
Our weather forecast can give you a great sense of what weather to expect in Butte in September 2025.
If you’re planning to visit Butte in the near future, we highly recommend that you review the 14 day weather forecast for Butte before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -3° / -12° | 4 | 10 | 17 | 39 mm | Awful | Butte in January |
| February | -4° / -13° | 5 | 4 | 20 | 46 mm | Awful | Butte in February |
| March | 1° / -7° | 6 | 7 | 19 | 66 mm | Awful | Butte in March |
| April | 6° / -4° | 7 | 7 | 16 | 94 mm | Awful | Butte in April |
| May | 12° / 1° | 11 | 13 | 8 | 115 mm | Awful | Butte in May |
| June | 18° / 5° | 9 | 20 | 1 | 111 mm | Ok | Butte in June |
| July | 25° / 9° | 3 | 28 | 0 | 44 mm | Perfect | Butte in July |
| August | 24° / 8° | 3 | 28 | 0 | 43 mm | Perfect | Butte in August |
| September | 19° / 5° | 3 | 26 | 1 | 48 mm | Good | Butte in September |
| October | 9° / -2° | 4 | 18 | 9 | 49 mm | Bad | Butte in October |
| November | 1° / -8° | 3 | 14 | 13 | 35 mm | Awful | Butte in November |
| December | -4° / -13° | 4 | 10 | 17 | 38 mm | Awful | Butte in December |