San Mateo (CA)
September
Weather in San Mateo, California for September 2027
Your guide to San Mateo weather in September - trends and predictions
In general, the average temperature in San Mateo at the beginning of September is 21.4 °C. As the month progressed, temperatures tended to moderately fall, reaching an average of 20.3 °C by the end of September.
Precipitation in San Mateo during September is a rare event, with an average of fewer than 2 rainy days.
Is September a good time to visit San Mateo? check out the best time to travel to San Mateo page.
✨ Is September a good time to visit San Mateo? – Ask the AI Weatherman
Temperatures
Rain 🌧️
More
29
Dry days
1
Rainy days
0
Snow days
21°/13°
Temperatures
16 km/h
Avg max wind
78 %
Avg humidity
San Mateo Weather September
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Temperatures trend during September in San Mateo
See the weather trend as well as the moving average line
September weather in San Mateo day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 | Cloudy | 20° /13° | 0.9 mm | 4 | |
| Sept. 2 | Sunny | 20° /13° | 0 mm | 6 | |
| Sept. 3 | Sunny | 22° /13° | 0.2 mm | 5 | |
| Sept. 4 | Sunny | 23° /14° | 0 mm | 6 | |
| Sept. 5 | Sunny | 22° /13° | 0 mm | 6 | |
| Sept. 6 | Overcast | 21° /13° | 0 mm | 6 | |
| Sept. 7 | Cloudy | 23° /13° | 0 mm | 6 | |
| Sept. 8 | Cloudy | 24° /13° | 0 mm | 5 | |
| Sept. 9 | Overcast | 23° /15° | 0 mm | 3 | |
| Sept. 10 | Overcast | 21° /15° | 0 mm | 5 | |
| Sept. 11 | Sunny | 19° /13° | 0 mm | 6 | |
| Sept. 12 | Sunny | 19° /13° | 0 mm | 6 | |
| Sept. 13 | Overcast | 19° /14° | 0 mm | 6 | |
| Sept. 14 | Sunny | 20° /13° | 0 mm | 5 | |
| Sept. 15 | Cloudy | 21° /13° | 0 mm | 6 | |
| Sept. 16 | Overcast | 19° /12° | 0.1 mm | 5 | |
| Sept. 17 | Overcast | 19° /13° | 0.1 mm | 5 | |
| Sept. 18 | Moderate rain | 19° /13° | 12 mm | 5 | |
| Sept. 19 | Overcast | 20° /13° | 0 mm | 5 | |
| Sept. 20 | Overcast | 19° /13° | 0 mm | 3 | |
| Sept. 21 | Cloudy | 19° /13° | 0 mm | 5 | |
| Sept. 22 | Cloudy | 20° /12° | 0 mm | 6 | |
| Sept. 23 | Partly cloudy | 25° /12° | 0 mm | 6.9 | |
| Sept. 24 | Partly cloudy | 22° /15° | 0 mm | 5 | |
| Sept. 25 | Cloudy | 18° /13° | 0 mm | 5 | |
| Sept. 26 | Overcast | 20° /12° | 0 mm | 5 | |
| Sept. 27 | Overcast | 20° /13° | 0 mm | 5 | |
| Sept. 28 | Overcast | 18° /13° | 0 mm | 5 | |
| Sept. 29 | Overcast | 20° /13° | 0 mm | 5 | |
| Sept. 30 | Partly cloudy | 23° /14° | 0 mm | 5 | |
| Next | |||||
Important Notice
Our weather forecast for San Mateo 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 Mateo forecast closer to your planned date for the most up-to-date weather information.
Change Month
San Mateo in September - FAQ
What are the expected maximum and minimum temperatures in San Mateo during September?
Enjoy moderate daytime temperatures of up to 21° 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 Mateo during September?
Expect minimal rainfall in San Mateo during September, with a total of 13.3 mm over approximately 1 days. This minimal precipitation is unlikely to significantly impact plans.
What are the typical wind conditions in San Mateo during September?
The average wind speed in San Mateo during September is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in San Mateo
Explore the daily rainfall trends and prepare for San Mateos September weather 💧
Typically, San Mateo has 1 rainy days in September with a total of 13.3 mm of rainfall.
UV exposure in San Mateo during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Get accurate weather forecasts for San Mateo, located at latitude 37.563 and longitude -122.326. Stay updated with localized weather information tailored for San Mateo.
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