Click on a day for an hourly weather forecast
The temperatures in Alta in September are quite cold with temperatures between 5°C and 10°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Alta 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 Alta can expect a few days of snow in September.
Our weather forecast can give you a great sense of what weather to expect in Alta in September 2025.
If you’re planning to visit Alta in the near future, we highly recommend that you review the 14 day weather forecast for Alta before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -7° / -11° | 5 | 7 | 19 | 50 mm | Awful | Alta in January |
| February | -6° / -12° | 4 | 6 | 18 | 41 mm | Awful | Alta in February |
| March | -3° / -9° | 5 | 5 | 21 | 61 mm | Awful | Alta in March |
| April | 0° / -6° | 6 | 6 | 18 | 57 mm | Awful | Alta in April |
| May | 5° / -1° | 7 | 13 | 11 | 62 mm | Awful | Alta in May |
| June | 11° / 5° | 8 | 20 | 2 | 89 mm | Awful | Alta in June |
| July | 15° / 9° | 8 | 23 | 0 | 94 mm | Ok | Alta in July |
| August | 14° / 8° | 5 | 26 | 0 | 64 mm | Good | Alta in August |
| September | 10° / 5° | 6 | 23 | 1 | 50 mm | Ok | Alta in September |
| October | 3° / 0° | 8 | 12 | 12 | 59 mm | Awful | Alta in October |
| November | -1° / -5° | 5 | 10 | 15 | 49 mm | Awful | Alta in November |
| December | -4° / -8° | 4 | 8 | 19 | 41 mm | Awful | Alta in December |