Pennington County (Rapid City)
September
Weather in Pennington County, South Dakota for September 2025
Your guide to Pennington County weather in September - trends and predictions
In general, the average temperature in Pennington County at the beginning of September is 29.3 °F. As the month progressed, temperatures tended to slightly increase, reaching an average of 29.7 °F by the end of September.
With an average of 5 rainy days, Pennington County experiences minimal rainfall in September.
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Temperatures
Rain 🌧️
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25
Dry days
5
Rainy days
0
Snow days
29°/15°
Temperatures
26 km/h
Avg max wind
35 %
Avg humidity
Pennington County Weather September
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Temperatures trend during September in Pennington County
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September weather in Pennington County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 28° /15° | 0 mm | 7 | |
| Sept. 2 | Sunny | 35° /19° | 0 mm | 9 | |
| Sept. 3 |  Overcast | 36° /20° | 0 mm | 8 | |
| Sept. 4 |  Heavy rain at times | 27° /19° | 1.3 mm | 6 | |
| Sept. 5 |  Partly cloudy | 25° /14° | 0 mm | 7 | |
| Sept. 6 | Sunny | 25° /12° | 0 mm | 6 | |
| Sept. 7 | Sunny | 29° /13° | 0 mm | 7 | |
| Sept. 8 | Sunny | 32° /14° | 0 mm | 8 | |
| Sept. 9 |  Cloudy | 34° /17° | 0 mm | 7 | |
| Sept. 10 | Partly cloudy | 34° /19° | 0 mm | 8 | |
| Sept. 11 | Partly cloudy | 33° /17° | 0 mm | 8 | |
| Sept. 12 |  Moderate or heavy rain shower | 33° /19° | 3.6 mm | 7 | |
| Sept. 13 | Moderate rain at times | 25° /14° | 0.5 mm | 6 | |
| Sept. 14 | Overcast | 29° /12° | 0 mm | 6 | |
| Sept. 15 | Partly cloudy | 30° /14° | 0 mm | 8 | |
| Sept. 16 | Partly cloudy | 31° /16° | 0.1 mm | 8 | |
| Sept. 17 | Cloudy | 31° /18° | 2.7 mm | 7 | |
| Sept. 18 | Sunny | 27° /14° | 8 mm | 7 | |
| Sept. 19 | Sunny | 26° /14° | 0 mm | 7 | |
| Sept. 20 | Sunny | 30° /13° | 0 mm | 8 | |
| Sept. 21 | Sunny | 19° /11° | 0 mm | 5 | |
| Sept. 22 | Sunny | 20° /7° | 0 mm | 6 | |
| Sept. 23 | Overcast | 23° /11° | 0 mm | 5 | |
| Sept. 24 | Sunny | 25° /12° | 0 mm | 7 | |
| Sept. 25 | Sunny | 30° /14° | 0 mm | 8 | |
| Sept. 26 | Sunny | 34° /19° | 0 mm | 8 | |
| Sept. 27 | Sunny | 28° /14° | 0 mm | 7 | |
| Sept. 28 | Sunny | 32° /18° | 0 mm | 8 | |
| Sept. 29 | Sunny | 35° /22° | 0 mm | 9 | |
| Sept. 30 | Sunny | 24° /10° | 0 mm | 6 | |
| Next | |||||
Important Notice
Our weather forecast for Pennington 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 Pennington County forecast closer to your planned date for the most up-to-date weather information.
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Pennington County in September - FAQ
What are the expected maximum and minimum temperatures in Pennington County during September?
During September, expect a variety of temperatures with highs around 29° and lows near 15°, suitable for diverse activities and preferences.
How much rainfall should be expected in Pennington County during September?
Expect minimal rainfall in Pennington County during September, with a total of 16.2 mm over approximately 5 days. This minimal precipitation is unlikely to significantly impact plans.
What are the typical wind conditions in Pennington County during September?
The average wind speed in Pennington County during September is 26 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Pennington County
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UV exposure in Pennington County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Pennington County?Get accurate weather forecasts for Pennington County, located at latitude 44.081 and longitude -103.231. Stay updated with localized weather information tailored for Pennington County.
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