Click on a day for an hourly weather forecast
The weather in Keystone in September is hot. The average temperatures are between 21°C and 27°C.
As it is almost never rain during September in Keystone the weather is perfect for hanging out outside and exploring all that Keystone has to offer.
Our weather forecast can give you a great sense of what weather to expect in Keystone in September 2024.
If you’re planning to visit Keystone in the near future, we highly recommend that you review the 14 day weather forecast for Keystone before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 20° / 13° | 3 | 28 | 0 | 61 mm | Good | Keystone in January |
| February | 20° / 12° | 2 | 26 | 0 | 55 mm | Good | Keystone in February |
| March | 20° / 13° | 2 | 29 | 0 | 37 mm | Good | Keystone in March |
| April | 21° / 14° | 1 | 29 | 0 | 16 mm | Good | Keystone in April |
| May | 22° / 15° | 1 | 31 | 0 | 9 mm | Good | Keystone in May |
| June | 24° / 17° | 0 | 30 | 0 | 5 mm | Perfect | Keystone in June |
| July | 26° / 19° | 1 | 30 | 0 | 16 mm | Perfect | Keystone in July |
| August | 27° / 20° | 0 | 31 | 0 | 12 mm | Perfect | Keystone in August |
| September | 27° / 21° | 0 | 30 | 0 | 12 mm | Perfect | Keystone in September |
| October | 25° / 19° | 1 | 30 | 0 | 17 mm | Perfect | Keystone in October |
| November | 23° / 15° | 1 | 29 | 0 | 24 mm | Perfect | Keystone in November |
| December | 19° / 12° | 2 | 29 | 0 | 61 mm | Good | Keystone in December |