Click on a day for an hourly weather forecast
The temperatures in Altoona in September are comfortable with low of 11°C and and high up to 24°C.
You can expect about 3 to 8 days of rain in Altoona 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 Altoona in September 2025.
If you’re planning to visit Altoona in the near future, we highly recommend that you review the 14 day weather forecast for Altoona before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 0° / -8° | 8 | 7 | 17 | 103 mm | Awful | Altoona in January |
| February | 2° / -6° | 8 | 6 | 15 | 119 mm | Awful | Altoona in February |
| March | 8° / -2° | 9 | 13 | 9 | 127 mm | Awful | Altoona in March |
| April | 15° / 3° | 10 | 17 | 3 | 143 mm | Bad | Altoona in April |
| May | 21° / 9° | 11 | 20 | 0 | 170 mm | Ok | Altoona in May |
| June | 26° / 12° | 8 | 22 | 0 | 145 mm | Good | Altoona in June |
| July | 29° / 15° | 9 | 22 | 0 | 147 mm | Ok | Altoona in July |
| August | 28° / 14° | 7 | 24 | 0 | 121 mm | Good | Altoona in August |
| September | 24° / 11° | 5 | 25 | 0 | 125 mm | Perfect | Altoona in September |
| October | 17° / 6° | 6 | 24 | 1 | 128 mm | Good | Altoona in October |
| November | 9° / -1° | 6 | 19 | 5 | 88 mm | Bad | Altoona in November |
| December | 4° / -4° | 9 | 11 | 11 | 124 mm | Awful | Altoona in December |