Santa Rosa
September
Weather in Santa Rosa for September 2025
Your guide to Santa Rosa weather in September - trends and predictions
In general, the average temperature in Santa Rosa at the beginning of September is 27.3 °F. As the month progressed, temperatures tended to moderately fall, reaching an average of 25.4 °F by the end of September.
With an average of 2 rainy days, Santa Rosa experiences minimal rainfall in September, ensuring that most days remain pleasantly dry.
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28
Dry days
2
Rainy days
0
Snow days
25°/10°
Temperatures
15 km/h
Avg max wind
73 %
Avg humidity
Santa Rosa in September average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  23° | 2  23° | 3 29° | 4  31° | 5  31° | 6 28° | 7 26° |
| 8  27° | 9 28° | 10 26° | 11  28° | 12 27° | 13 29° | 14 27° |
| 15 24° | 16 23° | 17 21° | 18 23° | 19 22° | 20 21° | 21 23° |
| 22 26° | 23 28° | 24 27° | 25 20° | 26 25° | 27 30° | 28 24° |
| 29 26° | 30 26° |
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Temperatures trend during September in Santa Rosa
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 | Mist | 23° /11° | 0 mm | 6 | |
| Sept. 2 | Patchy rain possible | 23° /11° | 0.1 mm | 6 | |
| Sept. 3 | Mist | 29° /11° | 0 mm | 7 | |
| Sept. 4 | Partly cloudy | 31° /13° | 0 mm | 8 | |
| Sept. 5 | Cloudy | 31° /12° | 0 mm | 7 | |
| Sept. 6 | Mist | 28° /10° | 0 mm | 7 | |
| Sept. 7 | Mist | 26° /9° | 0 mm | 7 | |
| Sept. 8 | Overcast | 27° /10° | 0 mm | 7 | |
| Sept. 9 | Mist | 28° /9° | 0 mm | 7 | |
| Sept. 10 | Cloudy | 26° /9° | 0 mm | 6 | |
| Sept. 11 | Sunny | 28° /10° | 0 mm | 8 | |
| Sept. 12 | Cloudy | 27° /10° | 0 mm | 7 | |
| Sept. 13 | Partly cloudy | 29° /11° | 0 mm | 8 | |
| Sept. 14 | Mist | 27° /11° | 0 mm | 7 | |
| Sept. 15 | Mist | 24° /10° | 0 mm | 6 | |
| Sept. 16 | Mist | 23° /10° | 0 mm | 6 | |
| Sept. 17 | Mist | 21° /10° | 0 mm | 5 | |
| Sept. 18 | Mist | 23° /11° | 0 mm | 5 | |
| Sept. 19 | Mist | 22° /12° | 0 mm | 6 | |
| Sept. 20 | Mist | 21° /10° | 0 mm | 5 | |
| Sept. 21 | Partly cloudy | 23° /9° | 0 mm | 6 | |
| Sept. 22 | Mist | 26° /8° | 0 mm | 6 | |
| Sept. 23 | Mist | 28° /9° | 0 mm | 7 | |
| Sept. 24 | Mist | 27° /10° | 0 mm | 7 | |
| Sept. 25 | Patchy rain possible | 20° /9° | 0.6 mm | 5 | |
| Sept. 26 | Mist | 25° /11° | 2.7 mm | 6 | |
| Sept. 27 | Sunny | 30° /10° | 0 mm | 8 | |
| Sept. 28 | Partly cloudy | 24° /9° | 0 mm | 6 | |
| Sept. 29 | Cloudy | 26° /10° | 0 mm | 6 | |
| Sept. 30 | Patchy rain possible | 26° /11° | 0 mm | 7 | |
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Important Notice
Our weather forecast for Santa Rosa 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 Santa Rosa forecast closer to your planned date for the most up-to-date weather information.
Santa Rosa in September - FAQ
What are the expected maximum and minimum temperatures in Santa Rosa during September?
Enjoy moderate daytime temperatures of up to 25° and cooler nights around 10°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Santa Rosa during September?
Rainfall in Santa Rosa during September is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 2 days seeing any precipitation. Planning without the concern for rain is generally straightforward during this very dry period.
What are the typical wind conditions in Santa Rosa during September?
The average wind speed in Santa Rosa during September is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Santa Rosa
Explore the daily rainfall trends and prepare for Santa Rosas September weather 💧
UV exposure in Santa Rosa during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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