Collin County (Frisco)
September
Weather in Collin County, Texas for September 2026
Your guide to Collin County weather in September - trends and predictions
So far, September 2026 in Collin County shows a warmer trend than usual by 2.6 °F.
Expect cooler weather in the next days in Collin County with the forecast suggesting a temperature of 34.2 °F, lower than the historical average.
In general, the average temperature in Collin County at the beginning of September is 35.6 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 32.1 °F by the end of September.
The climate of Collin County in September is notably wet, with an average of 12 rainy days, and a total of 78.5 mm of precipitation.
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Temperatures
Rain 🌧️
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18
Dry days
12
Rainy days
0
Snow days
34°/22°
Temperatures
20 km/h
Avg max wind
52 %
Avg humidity
Collin County Weather September
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Temperatures trend during September in Collin County
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September weather in Collin County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Partly cloudy | 36° /23° | 1.4 mm | 9 | |
| Sept. 2 |  Cloudy | 35° /24° | 3 mm | 8 | |
| Sept. 3 |  Thundery outbreaks possible | 34° /23° | 1.8 mm | 8 | |
| Sept. 4 |  Sunny | 35° /23° | 0.8 mm | 8 | |
| Sept. 5 | Partly cloudy | 37° /24° | 0.3 mm | 9 | |
| Sept. 6 | Thundery outbreaks possible | 36° /23° | 6.6 mm | 9 | |
| Sept. 7 | Sunny | 36° /23° | 0 mm | 9 | |
| Sept. 8 | Sunny | 37° /22° | 0.2 mm | 9 | |
| Sept. 9 | Sunny | 36° /21° | 0.1 mm | 9 | |
| Sept. 10 | Sunny | 36° /20° | 0.2 mm | 9 | |
| Sept. 11 |  Light rain shower | 34° /22° | 1.9 mm | 8 | |
| Sept. 12 | Sunny | 35° /22° | 16.5 mm | 8 | |
| Sept. 13 |  Overcast | 34° /24° | 0 mm | 8 | |
| Sept. 14 | Overcast | 34° /23° | 0.2 mm | 8 | |
| Sept. 15 | Cloudy | 34° /24° | 0.8 mm | 8 | |
| Sept. 16 | Sunny | 35° /23° | 0.3 mm | 8 | |
| Sept. 17 | Partly cloudy | 37° /29° | 0 mm | 7.8 | |
| Sept. 18 | Sunny | 37° /28° | 0 mm | 8.1 | |
| Sept. 19 | Sunny | 37° /27° | 0 mm | 8.6 | |
| Sept. 20 | Overcast | 36° /27° | 0 mm | 8.6 | |
| Sept. 21 | Sunny | 36° /27° | 0 mm | 9 | |
| Sept. 22 | Patchy rain possible | 35° /27° | 1 mm | 9 | |
| Sept. 23 | Overcast | 36° /28° | 0 mm | 9 | |
| Sept. 24 | Sunny | 33° /22° | 0.5 mm | 8 | |
| Sept. 25 | Sunny | 32° /20° | 0 mm | 8 | |
| Sept. 26 | Sunny | 31° /22° | 0 mm | 8 | |
| Sept. 27 | Sunny | 30° /21° | 0 mm | 8 | |
| Sept. 28 | Sunny | 32° /22° | 0 mm | 8 | |
| Sept. 29 | Sunny | 33° /22° | 0 mm | 8 | |
| Sept. 30 | Sunny | 34° /22° | 0 mm | 8 | |
| Next | |||||
Important Notice
Our weather forecast for Collin 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 Collin County forecast closer to your planned date for the most up-to-date weather information.
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Collin County in September - FAQ
What are the expected maximum and minimum temperatures in Collin County during September?
During September, expect a variety of temperatures with highs around 34° and lows near 22°, suitable for diverse activities and preferences.
How much rainfall should be expected in Collin County during September?
Moderate rainfall is anticipated in Collin County during September, with a total of 78.5 mm spread over approximately 12 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Collin County during September?
The average wind speed in Collin County during September is 20 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Collin County
Explore the daily rainfall trends and prepare for Collin Countys September weather 💧
Typically, Collin County has 12 rainy days in September with a total of 78.5 mm of rainfall.
UV exposure in Collin County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Collin County?Get accurate weather forecasts for Collin County, located at latitude 33.151 and longitude -96.824. Stay updated with localized weather information tailored for Collin County.
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