Stillwater (OK)
September
Weather in Stillwater, Oklahoma for September 2026
Your guide to Stillwater weather in September - trends and predictions
In general, the average temperature in Stillwater at the beginning of September is 28.3 °C. As the month progressed, temperatures tended to slightly increase, reaching an average of 28.6 °C by the end of September.
Stillwater experiences moderate rainfall in September, with an average of 10 rainy days and a total precipitation of 110.8 mm.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
20
Dry days
10
Rainy days
0
Snow days
30°/18°
Temperatures
20 km/h
Avg max wind
61 %
Avg humidity
Stillwater Weather September
Move between months or click on a day
Temperatures trend during September in Stillwater
See the weather trend as well as the moving average line
September weather in Stillwater day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 31° /19° | 9.8 mm | 7 | |
| Sept. 2 | Sunny | 29° /19° | 1.6 mm | 7 | |
| Sept. 3 |  Overcast | 28° /18° | 0 mm | 7 | |
| Sept. 4 | Overcast | 29° /19° | 0 mm | 7 | |
| Sept. 5 | Overcast | 26° /17° | 0 mm | 6 | |
| Sept. 6 |  Cloudy | 29° /16° | 0 mm | 7 | |
| Sept. 7 |  Partly cloudy | 26° /15° | 0 mm | 6 | |
| Sept. 8 | Sunny | 28° /14° | 0 mm | 7 | |
| Sept. 9 | Sunny | 28° /15° | 16.5 mm | 7 | |
| Sept. 10 | Sunny | 29° /16° | 5.2 mm | 7 | |
| Sept. 11 | Partly cloudy | 34° /16° | 0 mm | 8 | |
| Sept. 12 | Partly cloudy | 34° /18° | 0 mm | 8 | |
| Sept. 13 | Sunny | 34° /18° | 0 mm | 8 | |
| Sept. 14 |  Moderate or heavy rain shower | 31° /19° | 1.6 mm | 7 | |
| Sept. 15 |  Patchy rain possible | 33° /19° | 0.1 mm | 8 | |
| Sept. 16 | Overcast | 34° /19° | 0 mm | 8 | |
| Sept. 17 | Overcast | 33° /20° | 0 mm | 7 | |
| Sept. 18 | Overcast | 33° /20° | 9.4 mm | 7 | |
| Sept. 19 |  Heavy rain at times | 36° /21° | 0.6 mm | 8 | |
| Sept. 20 | Cloudy | 37° /21° | 0.5 mm | 9 | |
| Sept. 21 | Partly cloudy | 30° /22° | 3.6 mm | 7 | |
| Sept. 22 | Moderate or heavy rain shower | 31° /18° | 9.3 mm | 8 | |
| Sept. 23 | Moderate or heavy rain shower | 24° /16° | 41.8 mm | 5 | |
| Sept. 24 | Moderate or heavy rain shower | 25° /15° | 10.8 mm | 6 | |
| Sept. 25 | Sunny | 28° /14° | 0 mm | 7 | |
| Sept. 26 | Sunny | 28° /14° | 0 mm | 7 | |
| Sept. 27 | Sunny | 29° /13° | 0 mm | 8 | |
| Sept. 28 | Overcast | 31° /16° | 0 mm | 7 | |
| Sept. 29 | Partly cloudy | 29° /15° | 0 mm | 7 | |
| Sept. 30 |  Mist | 30° /15° | 0 mm | 7 | |
| Next | |||||
Important Notice
Our weather forecast for Stillwater 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 Stillwater forecast closer to your planned date for the most up-to-date weather information.
Change Month
Stillwater in September - FAQ
What are the expected maximum and minimum temperatures in Stillwater during September?
Expect warm days with temperatures around 30°, cooling to mild conditions of 18° after sunset. Perfect for those who enjoy warm weather.
How much rainfall should be expected in Stillwater during September?
Significant rainfall exceeding 110.8 mm is expected in Stillwater during September, occurring over more than 10 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Stillwater during September?
The average wind speed in Stillwater during September is 20 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Stillwater
Explore the daily rainfall trends and prepare for Stillwaters September weather 💧
Typically, Stillwater has 10 rainy days in September with a total of 110.8 mm of rainfall.
UV exposure in Stillwater during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Quick links
More Stillwater weather pages
You are here
Where is Stillwater?Get accurate weather forecasts for Stillwater, located at latitude 36.116 and longitude -97.058. Stay updated with localized weather information tailored for Stillwater.
Found a mistake?
We appreciate your attention to details. Tell us here.