Collin County
September
Weather in Collin County for September 2025
Your guide to Collin County weather in September - trends and predictions
In general, the average temperature in Collin County at the beginning of September is 34.9 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 33.6 °F by the end of September.
The climate of Collin County in September is notably wet, with an average of 11 rainy days.
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19
Dry days
11
Rainy days
0
Snow days
36°/23°
Temperatures
23 km/h
Avg max wind
48 %
Avg humidity
Collin County in September average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  35° | 2  36° | 3  32° | 4  31° | 5 35° | 6 37° | 7 38° |
| 8 38° | 9 36° | 10 35° | 11  31° | 12  31° | 13 32° | 14  34° |
| 15 32° | 16 32° | 17 34° | 18 36° | 19 37° | 20  37° | 21 37° |
| 22 35° | 23 32° | 24 35° | 25 31° | 26 33° | 27 33° | 28 33° |
| 29 35° | 30 35° |
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Temperatures trend during September in Collin 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 | Partly cloudy | 35° /23° | 0.7 mm | 8 | |
| Sept. 2 | Cloudy | 36° /23° | 0.3 mm | 8 | |
| Sept. 3 | Thundery outbreaks possible | 32° /23° | 4 mm | 7 | |
| Sept. 4 | Sunny | 31° /22° | 1.8 mm | 8 | |
| Sept. 5 | Partly cloudy | 35° /22° | 0.7 mm | 8 | |
| Sept. 6 | Thundery outbreaks possible | 37° /25° | 0 mm | 9 | |
| Sept. 7 | Sunny | 38° /24° | 0 mm | 9 | |
| Sept. 8 | Sunny | 38° /24° | 0.2 mm | 10 | |
| Sept. 9 | Sunny | 36° /21° | 0 mm | 9 | |
| Sept. 10 | Partly cloudy | 35° /19° | 0 mm | 9 | |
| Sept. 11 | Light rain shower | 31° /21° | 2.2 mm | 7 | |
| Sept. 12 | Moderate or heavy rain shower | 31° /21° | 29 mm | 8 | |
| Sept. 13 | Cloudy | 32° /22° | 0 mm | 8 | |
| Sept. 14 | Overcast | 34° /21° | 2.5 mm | 8 | |
| Sept. 15 | Cloudy | 32° /22° | 1.7 mm | 7 | |
| Sept. 16 | Partly cloudy | 32° /21° | 0.6 mm | 8 | |
| Sept. 17 | Sunny | 34° /20° | 0 mm | 8 | |
| Sept. 18 | Sunny | 36° /23° | 0 mm | 9 | |
| Sept. 19 | Cloudy | 37° /23° | 0 mm | 9 | |
| Sept. 20 | Heavy rain at times | 37° /23° | 1.3 mm | 9 | |
| Sept. 21 | Thundery outbreaks possible | 37° /24° | 0.7 mm | 9 | |
| Sept. 22 | Thundery outbreaks possible | 35° /23° | 2.2 mm | 8 | |
| Sept. 23 | Thundery outbreaks possible | 32° /24° | 9.3 mm | 7 | |
| Sept. 24 | Sunny | 35° /23° | 2.7 mm | 8 | |
| Sept. 25 | Light rain shower | 31° /21° | 3.7 mm | 7 | |
| Sept. 26 | Sunny | 33° /18° | 0 mm | 9 | |
| Sept. 27 | Partly cloudy | 33° /19° | 0 mm | 9 | |
| Sept. 28 | Partly cloudy | 33° /20° | 0 mm | 8 | |
| Sept. 29 | Sunny | 35° /21° | 0 mm | 8 | |
| Sept. 30 | Sunny | 35° /21° | 0 mm | 9 | |
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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.
Collin County in September - FAQ
What are the expected maximum and minimum temperatures in Collin County during September?
With daytime temperatures soaring above 36° and not dropping much below 23° at night, September in Collin County is quite hot. Staying hydrated and avoiding peak sun hours is advisable.
How much rainfall should be expected in Collin County during September?
Moderate rainfall is anticipated in Collin County during September, with a total of 89.3 mm spread over approximately 11 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 23 km/h, suggesting breezy to windy conditions, depending on your activities.
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Where is Collin County?Get accurate weather forecasts for Collin County, located at latitude 33.02 and longitude -96.699. Stay updated with localized weather information tailored for Collin County.
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