San Luis Obispo
September
Weather in San Luis Obispo for September 2025
Your guide to San Luis Obispo weather in September - trends and predictions
In general, the average temperature in San Luis Obispo at the beginning of September is 28.3 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 26 °F by the end of September.
Precipitation in San Luis Obispo during September is a rare event, with an average of fewer than 2 rainy days.
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Temperatures
Rain 🌧️
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30
Dry days
0
Rainy days
0
Snow days
25°/13°
Temperatures
13 km/h
Avg max wind
63 %
Avg humidity
San Luis Obispo Weather September
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| Sun. | Mon. | Tue. | Wed. | Thu. | Fri. | Sat. |
|---|---|---|---|---|---|---|
| 1  24° | 2 26° | 3 27° | 4 27° | 5 31° | 6 32° | |
| 7 31° | 8 31° | 9 28° | 10 23° | 11 25° | 12 25° | 13 22° |
| 14 21° | 15  19° | 16  18° | 17  20° | 18 18° | 19 16° | 20  19° |
| 21 20° | 22 25° | 23 30° | 24 26° | 25 22° | 26 24° | 27 28° |
| 28 23° | 29 27° | 30 32° |
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Temperatures trend during September in San Luis Obispo
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 | Sunny | 24° /12° | 0 mm | 6 | |
| Sept. 2 | Sunny | 26° /14° | 0 mm | 7 | |
| Sept. 3 | Sunny | 27° /15° | 0 mm | 7 | |
| Sept. 4 | Sunny | 27° /16° | 0 mm | 7 | |
| Sept. 5 | Sunny | 31° /18° | 0 mm | 8 | |
| Sept. 6 | Sunny | 32° /18° | 0 mm | 8 | |
| Sept. 7 | Sunny | 31° /18° | 0 mm | 8 | |
| Sept. 8 | Sunny | 31° /18° | 0 mm | 8 | |
| Sept. 9 | Sunny | 28° /13° | 0 mm | 7 | |
| Sept. 10 | Sunny | 23° /10° | 0 mm | 6 | |
| Sept. 11 | Sunny | 25° /10° | 0 mm | 7 | |
| Sept. 12 | Sunny | 25° /11° | 0 mm | 7 | |
| Sept. 13 | Sunny | 22° /11° | 0 mm | 6 | |
| Sept. 14 | Sunny | 21° /11° | 0 mm | 6 | |
| Sept. 15 | Patchy rain possible | 19° /10° | 0 mm | 4 | |
| Sept. 16 | Partly cloudy | 18° /10° | 0 mm | 5 | |
| Sept. 17 | Mist | 20° /12° | 0 mm | 5 | |
| Sept. 18 | Mist | 18° /10° | 0 mm | 4 | |
| Sept. 19 | Mist | 16° /11° | 0 mm | 4 | |
| Sept. 20 | Thundery outbreaks possible | 19° /10° | 0 mm | 4 | |
| Sept. 21 | Mist | 20° /10° | 0 mm | 5 | |
| Sept. 22 | Partly cloudy | 25° /11° | 0 mm | 7 | |
| Sept. 23 | Partly cloudy | 30° /16° | 0 mm | 8 | |
| Sept. 24 | Partly cloudy | 26° /15° | 0 mm | 7 | |
| Sept. 25 | Partly cloudy | 22° /11° | 0 mm | 6 | |
| Sept. 26 | Partly cloudy | 24° /11° | 0 mm | 6 | |
| Sept. 27 | Partly cloudy | 28° /14° | 0 mm | 7 | |
| Sept. 28 | Partly cloudy | 23° /11° | 0 mm | 6 | |
| Sept. 29 | Partly cloudy | 27° /12° | 0 mm | 7 | |
| Sept. 30 | Partly cloudy | 32° /15° | 0 mm | 8 | |
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Important Notice
Our weather forecast for San Luis Obispo 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 San Luis Obispo forecast closer to your planned date for the most up-to-date weather information.
San Luis Obispo in September - FAQ
What are the expected maximum and minimum temperatures in San Luis Obispo during September?
Enjoy moderate daytime temperatures of up to 25° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in San Luis Obispo during September?
Rainfall in San Luis Obispo during September is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 0 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 San Luis Obispo during September?
The average wind speed in San Luis Obispo during September is 13 km/h, suggesting breezy to windy conditions, depending on your activities.
UV exposure in San Luis Obispo during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is San Luis Obispo?Get accurate weather forecasts for San Luis Obispo, located at latitude 35.283 and longitude -120.66. Stay updated with localized weather information tailored for San Luis Obispo.
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