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Hourly Forecast
Daylight Hours
06:57
Sunrise
19:09
Sunset
Moon
Waxing Crescent
12:46
Moonrise
21:28
Moonset
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Weather in San Mateo today, September 16, 2026
Expect a muted, overcast feel in San Mateo on September 16, 2026 as cloud persists. Brighter breaks, if they arrive, should stay brief. The first half of the day looks overcast, as cloud amounts reach about 100% around 08:00. Brighter weather, if it comes, waits until later.
The temperature range runs from about 14°C up to 23°C. Relative humidity sits between 70% and 98%, reaching its peak around 06:00. Expect gentle winds, highest near 08:00 at 7.2 km/h.
The afternoon keeps an overcast feel, as cloud reaches about 100% around 13:00. Outdoor plans may still want a flexible backup. Expect visibility near 12.7 km, with poorer spells close to 0.2 km. Expect sunrise at 06:57, sunset at 19:09, and 12 hours 11 minutes of sunlight today overall.
Taken together, overcast skies in San Mateo on September 16, 2026 favour indoor or covered options, with temperatures near 23°C.
Frequently asked questions about weather in San Mateo
How warm does it get in San Mateo?
The warmest month in San Mateo is September, with average high temperatures of 24°C. The average temperature during this period is around 18°C.
How cold does it get in San Mateo?
The coldest month in San Mateo is February, with average low temperatures of 8°C. The average temperature during this period is around 11°C.
What is the wettest time of year in San Mateo?
The wettest month in San Mateo is January, with an average of 113mm of precipitation.
What is the driest time of year in San Mateo?
The driest month in San Mateo is July, with an average of 0mm of precipitation.
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