Onondaga County (Syracuse)
September
Weather in Onondaga County for September 2025
Your guide to Onondaga County weather in September - trends and predictions
In general, the average temperature in Onondaga County at the beginning of September is 21.6 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 19.3 °F by the end of September.
Onondaga County experiences moderate rainfall in September, with an average of 8 rainy days and a total precipitation of 141.1 mm.
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Temperatures
Rain 🌧️
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22
Dry days
8
Rainy days
0
Snow days
22°/13°
Temperatures
14 km/h
Avg max wind
77 %
Avg humidity
Onondaga County in September average weather
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| Sun. | Mon. | Tue. | Wed. | Thu. | Fri. | Sat. |
|---|---|---|---|---|---|---|
| 1  25° | 2 16° | 3  20° | 4  23° | 5 23° | 6 25° | |
| 7 19° | 8 16° | 9  17° | 10  19° | 11  23° | 12 26° | 13 26° |
| 14 26° | 15  26° | 16 26° | 17  25° | 18 26° | 19 23° | 20 24° |
| 21 24° | 22 22° | 23 15° | 24 20° | 25  18° | 26 21° | 27 18° |
| 28 19° | 29  18° | 30 21° |
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Temperatures trend during September in Onondaga County
See the weather trend as well as the moving average line
September weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 | Light rain shower | 25° /13° | 2.7 mm | 6 | |
| Sept. 2 | Patchy rain possible | 16° /9° | 0.5 mm | 4 | |
| Sept. 3 | Partly cloudy | 20° /7° | 0 mm | 6 | |
| Sept. 4 | Sunny | 23° /10° | 0 mm | 6 | |
| Sept. 5 | Sunny | 23° /11° | 0 mm | 6 | |
| Sept. 6 | Partly cloudy | 25° /12° | 0 mm | 7 | |
| Sept. 7 | Light rain shower | 19° /8° | 22.2 mm | 4 | |
| Sept. 8 | Patchy rain possible | 16° /6° | 0.2 mm | 4 | |
| Sept. 9 | Moderate or heavy rain with thunder | 17° /10° | 8.4 mm | 4 | |
| Sept. 10 | Mist | 19° /11° | 0 mm | 4 | |
| Sept. 11 | Overcast | 23° /9° | 0 mm | 5 | |
| Sept. 12 | Partly cloudy | 26° /14° | 0 mm | 7 | |
| Sept. 13 | Sunny | 26° /15° | 0 mm | 7 | |
| Sept. 14 | Sunny | 26° /15° | 0 mm | 7 | |
| Sept. 15 | Moderate rain at times | 26° /15° | 2 mm | 6 | |
| Sept. 16 | Partly cloudy | 26° /15° | 0 mm | 7 | |
| Sept. 17 | Cloudy | 25° /15° | 0 mm | 6 | |
| Sept. 18 | Cloudy | 26° /13° | 0 mm | 6 | |
| Sept. 19 | Fog | 23° /15° | 0 mm | 5 | |
| Sept. 20 | Fog | 24° /15° | 0 mm | 5 | |
| Sept. 21 | Cloudy | 24° /15° | 0 mm | 5 | |
| Sept. 22 | Overcast | 22° /15° | 0 mm | 5 | |
| Sept. 23 | Moderate or heavy rain shower | 15° /14° | 21 mm | 4 | |
| Sept. 24 | Overcast | 20° /15° | 0 mm | 5 | |
| Sept. 25 | Heavy rain | 18° /14° | 57.9 mm | 4 | |
| Sept. 26 | Patchy rain possible | 21° /14° | 6.5 mm | 5 | |
| Sept. 27 | Fog | 18° /11° | 0 mm | 4 | |
| Sept. 28 | Overcast | 19° /16° | 0 mm | 4 | |
| Sept. 29 | Light rain | 18° /16° | 19.7 mm | 4 | |
| Sept. 30 | Mist | 21° /16° | 0 mm | 5 | |
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Important Notice
Our weather forecast for Onondaga County 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 Onondaga County forecast closer to your planned date for the most up-to-date weather information.
Onondaga County in September - FAQ
What are the expected maximum and minimum temperatures in Onondaga County during September?
Enjoy moderate daytime temperatures of up to 22° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Onondaga County during September?
Significant rainfall exceeding 141.1 mm is expected in Onondaga County during September, occurring over more than 8 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Onondaga County during September?
The average wind speed in Onondaga County during September is 14 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Onondaga County
Explore the daily rainfall trends and prepare for Onondaga Countys September weather 💧
UV exposure in Onondaga County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Onondaga County?Get accurate weather forecasts for Onondaga County, located at latitude 43.048 and longitude -76.147. Stay updated with localized weather information tailored for Onondaga County.
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