Riley County (Manhattan)
September
Weather in Riley County, Kansas for September 2026
Your guide to Riley County weather in September - trends and predictions
So far, September 2026 in Riley County shows a warmer trend than usual by 4.3 °F.
Expect cooler weather in the next days in Riley County with the forecast suggesting a temperature of 28.6 °F, lower than the historical average.
In general, the average temperature in Riley County at the beginning of September is 31.4 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 27.1 °F by the end of September.
Riley County experiences moderate rainfall in September, with an average of 9 rainy days and a total precipitation of 113.9 mm.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
21
Dry days
9
Rainy days
0
Snow days
27°/16°
Temperatures
23 km/h
Avg max wind
76 %
Avg humidity
Riley County Weather September
Move between months or click on a day
Temperatures trend during September in Riley County
See the weather trend as well as the moving average line
September weather in Riley County day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Light rain shower | 29° /19° | 6.2 mm | 5 | |
| Sept. 2 |  Mist | 32° /19° | 0 mm | 7 | |
| Sept. 3 | Fog | 33° /19° | 0 mm | 8 | |
| Sept. 4 | Fog | 33° /18° | 0 mm | 7 | |
| Sept. 5 |  Moderate rain at times | 28° /18° | 1.7 mm | 4 | |
| Sept. 6 | Mist | 32° /14° | 0.3 mm | 8 | |
| Sept. 7 | Mist | 33° /14° | 0 mm | 8 | |
| Sept. 8 |  Moderate rain | 30° /19° | 13.9 mm | 6 | |
| Sept. 9 | Light rain shower | 29° /18° | 7.2 mm | 5 | |
| Sept. 10 |  Thundery outbreaks possible | 28° /18° | 0.6 mm | 4 | |
| Sept. 11 |  Cloudy | 33° /17° | 0 mm | 8 | |
| Sept. 12 |  Sunny | 32° /19° | 9.5 mm | 7 | |
| Sept. 13 | Sunny | 30° /17° | 1.7 mm | 5 | |
| Sept. 14 |  Overcast | 31° /19° | 2.1 mm | 5 | |
| Sept. 15 | Cloudy | 31° /18° | 14.3 mm | 4 | |
| Sept. 16 | Light rain shower | 28° /17° | 6.7 mm | 5 | |
| Sept. 17 | Sunny | 34° /25° | 0 mm | 7 | |
| Sept. 18 | Sunny | 35° /26° | 0 mm | 6.8 | |
| Sept. 19 | Light rain shower | 34° /22° | 10 mm | 7.1 | |
| Sept. 20 | Light rain shower | 25° /19° | 5.1 mm | 5 | |
| Sept. 21 | Sunny | 25° /19° | 0 mm | 7 | |
| Sept. 22 | Sunny | 29° /17° | 0 mm | 6 | |
| Sept. 23 | Sunny | 28° /19° | 1 mm | 6 | |
| Sept. 24 | Sunny | 22° /13° | 0 mm | 6 | |
| Sept. 25 | Sunny | 26° /13° | 0 mm | 7 | |
| Sept. 26 | Sunny | 30° /16° | 0 mm | 7 | |
| Sept. 27 | Sunny | 31° /20° | 0 mm | 8 | |
| Sept. 28 | Sunny | 31° /19° | 0 mm | 8 | |
| Sept. 29 | Overcast | 23° /14° | 0 mm | 5 | |
| Sept. 30 | Overcast | 27° /15° | 0 mm | 2 | |
| Next | |||||
Important Notice
Our weather forecast for Riley 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 Riley County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Riley County in September - FAQ
What are the expected maximum and minimum temperatures in Riley County during September?
During September, expect a variety of temperatures with highs around 27° and lows near 16°, suitable for diverse activities and preferences.
How much rainfall should be expected in Riley County during September?
Significant rainfall exceeding 113.9 mm is expected in Riley County during September, occurring over more than 9 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Riley County during September?
The average wind speed in Riley County during September is 23 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Riley County
Explore the daily rainfall trends and prepare for Riley Countys September weather 💧
Typically, Riley County has 9 rainy days in September with a total of 113.9 mm of rainfall.
UV exposure in Riley County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Top locations in Riley County
Select a location for an accurate weather forecast
More Locations Quick links
More Riley County weather pages
You are here
Where is Riley County?Get accurate weather forecasts for Riley County, located at latitude 39.184 and longitude -96.572. Stay updated with localized weather information tailored for Riley County.
Found a mistake?
We appreciate your attention to details. Tell us here.