San Mateo County (San Mateo)
January
Weather in San Mateo County, California for January 2026
Your guide to San Mateo County weather in January - trends and predictions
In general, the average temperature in San Mateo County at the beginning of January is 12.6 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 10.4 °F by the end of January.
With an average of 2 rainy days, San Mateo County experiences minimal rainfall in January.
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Temperatures
Rain 🌧️
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29
Dry days
2
Rainy days
0
Snow days
12°/7°
Temperatures
12 km/h
Avg max wind
79 %
Avg humidity
San Mateo County Weather January
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Temperatures trend during January in San Mateo County
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January weather in San Mateo County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Jan. 1 |  Cloudy | 11° /7° | 0 mm | 3 | |
| Jan. 2 |  Partly cloudy | 15° /10° | 0 mm | 5 | |
| Jan. 3 |  Heavy rain at times | 12° /10° | 11.5 mm | 3 | |
| Jan. 4 |  Overcast | 12° /7° | 0 mm | 3 | |
| Jan. 5 | Overcast | 11° /7° | 0 mm | 3 | |
| Jan. 6 | Overcast | 13° /9° | 0 mm | 3 | |
| Jan. 7 |  Sunny | 14° /10° | 0 mm | 4 | |
| Jan. 8 | Cloudy | 13° /10° | 0 mm | 3 | |
| Jan. 9 | Overcast | 16° /7° | 0 mm | 4 | |
| Jan. 10 | Cloudy | 14° /7° | 0 mm | 3 | |
| Jan. 11 | Overcast | 14° /7° | 0 mm | 3 | |
| Jan. 12 | Sunny | 13° /8° | 0 mm | 4 | |
| Jan. 13 | Sunny | 12° /6° | 0 mm | 4 | |
| Jan. 14 | Sunny | 13° /6° | 0 mm | 4 | |
| Jan. 15 | Cloudy | 14° /5° | 0 mm | 3 | |
| Jan. 16 | Partly cloudy | 13° /5° | 0 mm | 4 | |
| Jan. 17 | Overcast | 10° /5° | 0 mm | 3 | |
| Jan. 18 | Overcast | 10° /6° | 0 mm | 3 | |
| Jan. 19 | Overcast | 8° /6° | 0 mm | 2 | |
| Jan. 20 | Overcast | 12° /5° | 0 mm | 3 | |
| Jan. 21 | Partly cloudy | 14° /5° | 0 mm | 4 | |
| Jan. 22 | Sunny | 14° /6° | 0 mm | 4 | |
| Jan. 23 | Sunny | 15° /6° | 0 mm | 5 | |
| Jan. 24 | Overcast | 13° /6° | 0 mm | 3 | |
| Jan. 25 |  Patchy rain possible | 10° /6° | 0.2 mm | 3 | |
| Jan. 26 | Partly cloudy | 10° /7° | 0 mm | 4 | |
| Jan. 27 | Sunny | 13° /5° | 0 mm | 4 | |
| Jan. 28 | Overcast | 10° /6° | 0 mm | 3 | |
| Jan. 29 | Overcast | 9° /6° | 0 mm | 2 | |
| Jan. 30 | Overcast | 11° /7° | 0 mm | 3 | |
| Jan. 31 |  Moderate rain | 10° /8° | 8.3 mm | 3 | |
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Important Notice
Our weather forecast for San Mateo County in January 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 County forecast closer to your planned date for the most up-to-date weather information.
Change Month
San Mateo County in January - FAQ
What are the expected maximum and minimum temperatures in San Mateo County during January?
During January, expect a variety of temperatures with highs around 12° and lows near 7°, suitable for diverse activities and preferences.
How much rainfall should be expected in San Mateo County during January?
Expect minimal rainfall in San Mateo County during January, with a total of 20 mm over approximately 2 days. This minimal precipitation is unlikely to significantly impact plans.
What are the typical wind conditions in San Mateo County during January?
The average wind speed in San Mateo County during January is 12 km/h, suggesting breezy to windy conditions, depending on your activities.
January rainfall patterns in San Mateo County
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Where is San Mateo County?Get accurate weather forecasts for San Mateo County, located at latitude 37.563 and longitude -122.326. Stay updated with localized weather information tailored for San Mateo County.
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