Click on a day for an hourly weather forecast
The temperatures in American Canyon in September are comfortable with low of 15°C and and high up to 29°C.
You can expect up to 3 rainy days in American Canyon during the month of September.
Our weather forecast can give you a great sense of what weather to expect in American Canyon in September 2025.
If you’re planning to visit American Canyon in the near future, we highly recommend that you review the 14 day weather forecast for American Canyon before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 14° / 6° | 6 | 25 | 0 | 114 mm | Good | American Canyon in January |
| February | 16° / 7° | 5 | 23 | 0 | 101 mm | Good | American Canyon in February |
| March | 17° / 7° | 7 | 24 | 0 | 105 mm | Ok | American Canyon in March |
| April | 20° / 9° | 3 | 27 | 0 | 31 mm | Good | American Canyon in April |
| May | 23° / 11° | 2 | 29 | 0 | 16 mm | Perfect | American Canyon in May |
| June | 27° / 13° | 1 | 29 | 0 | 6 mm | Perfect | American Canyon in June |
| July | 29° / 14° | 0 | 31 | 0 | 1 mm | Good | American Canyon in July |
| August | 29° / 14° | 0 | 31 | 0 | 0 mm | Good | American Canyon in August |
| September | 29° / 15° | 0 | 30 | 0 | 4 mm | Good | American Canyon in September |
| October | 24° / 13° | 2 | 29 | 0 | 38 mm | Perfect | American Canyon in October |
| November | 18° / 9° | 4 | 26 | 0 | 57 mm | Good | American Canyon in November |
| December | 13° / 6° | 7 | 24 | 0 | 116 mm | Bad | American Canyon in December |