Altoona (PA)
September
Weather in Altoona, Pennsylvania for September 2025
Your guide to Altoona weather in September - trends and predictions
In general, the average temperature in Altoona at the beginning of September is 22.4 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 18.6 °F by the end of September.
The climate of Altoona in September is notably wet, with an average of 14 rainy days, and a total of 152.9 mm of precipitation.
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Temperatures
Rain 🌧️
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16
Dry days
14
Rainy days
0
Snow days
22°/12°
Temperatures
12 km/h
Avg max wind
78 %
Avg humidity
Altoona Weather September
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Temperatures trend during September in Altoona
See the weather trend as well as the moving average line
September weather in Altoona day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Patchy rain possible | 26° /17° | 0.3 mm | 6 | |
| Sept. 2 |  Sunny | 21° /11° | 0 mm | 6 | |
| Sept. 3 | Sunny | 21° /7° | 0 mm | 6 | |
| Sept. 4 | Sunny | 22° /8° | 0 mm | 6 | |
| Sept. 5 | Sunny | 23° /9° | 0 mm | 6 | |
| Sept. 6 | Sunny | 26° /9° | 0 mm | 7 | |
| Sept. 7 |  Moderate or heavy rain shower | 18° /8° | 6.6 mm | 4 | |
| Sept. 8 |  Overcast | 18° /6° | 0 mm | 4 | |
| Sept. 9 | Moderate rain at times | 22° /6° | 0.6 mm | 5 | |
| Sept. 10 | Sunny | 25° /10° | 0 mm | 6 | |
| Sept. 11 | Sunny | 26° /12° | 0 mm | 7 | |
| Sept. 12 | Sunny | 25° /11° | 0 mm | 7 | |
| Sept. 13 |  Partly cloudy | 24° /11° | 0 mm | 6 | |
| Sept. 14 | Sunny | 27° /12° | 0 mm | 7 | |
| Sept. 15 | Sunny | 25° /12° | 0 mm | 7 | |
| Sept. 16 | Overcast | 23° /12° | 0 mm | 5 | |
| Sept. 17 | Overcast | 21° /13° | 0.1 mm | 5 | |
| Sept. 18 | Overcast | 21° /14° | 2.3 mm | 5 | |
| Sept. 19 |  Cloudy | 25° /14° | 0 mm | 5 | |
| Sept. 20 | Sunny | 27° /14° | 0 mm | 7 | |
| Sept. 21 | Moderate or heavy rain shower | 23° /15° | 16.1 mm | 5 | |
| Sept. 22 | Patchy rain possible | 21° /15° | 2.2 mm | 5 | |
| Sept. 23 | Moderate or heavy rain shower | 17° /15° | 16.5 mm | 4 | |
| Sept. 24 | Moderate or heavy rain shower | 15° /14° | 18.7 mm | 4 | |
| Sept. 25 | Moderate or heavy rain shower | 20° /15° | 13 mm | 5 | |
| Sept. 26 | Moderate or heavy rain shower | 23° /17° | 10.1 mm | 5 | |
| Sept. 27 | Moderate or heavy rain shower | 20° /16° | 10.5 mm | 5 | |
| Sept. 28 | Moderate rain at times | 20° /17° | 6.8 mm | 5 | |
| Sept. 29 | Moderate or heavy rain shower | 18° /14° | 15.6 mm | 4 | |
| Sept. 30 |  Moderate rain | 14° /13° | 33.5 mm | 3 | |
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Important Notice
Our weather forecast for Altoona in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Altoona forecast closer to your planned date for the most up-to-date weather information.
Change Month
Altoona in September - FAQ
What are the expected maximum and minimum temperatures in Altoona during September?
Enjoy moderate daytime temperatures of up to 22° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Altoona during September?
Significant rainfall exceeding 152.9 mm is expected in Altoona during September, occurring over more than 14 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Altoona during September?
The average wind speed in Altoona during September is 12 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Altoona
Explore the daily rainfall trends and prepare for Altoonas September weather 💧
UV exposure in Altoona during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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