San Mateo Weather in January

January in San Mateo typically sees daytime highs of 15°C (59°F) and nighttime lows of 6°C (43°F). Rainfall is also possible this month, so it's worth packing an umbrella.

Rainfall in San Mateo in January

On average, there are about 9 days with rain during this month, averaging 63 mm (2.5 in). A fairly balanced picture this month, some wet days but nothing too extreme in terms of intensity.

Temperature in San Mateo in January

In January, San Mateo gets moderate temperatures, with highs of 15°C (59°F). Nights cool to around 6°C (43°F). The difference between afternoon and evening temperatures is usually noticeable. With overnight lows of 6°C (43°F), nights are cold. The cold air does make for deep, comfortable sleep if you have enough blankets.

Sunshine in San Mateo in January

The month experiences a moderate amount of sunlight, with 186 hours of sunshine. This provides a nice balance between sunshine and clouds.

Wind Speed in San Mateo in January

Average wind speeds reach 3 m/s (6 knots) in January, creating light breezes that feel pleasant throughout the day. Some days are calmer, while others bring slightly more active breezes.

Average water temperature in January

The water sits at 12°C (54°F) this month, which is well below what most people consider swimmable. Wetsuits help, but expect it to still feel cold.

If you're looking for dry conditions and comfortable temperatures, January may not be the ideal month to visit San Mateo. Our weather planner can help you explore destinations with more pleasant weather conditions.

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• January
• February
• March
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• May
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• December

For a detailed overview over the year and the best time to visit the United States of America, check out our San Mateo's climate page.

San Mateo Temperature in January

Min Temperature 6°C (43°F)  

Max Temperature 15°C (59°F)  

Water Temperature 12°C (54°F) *  

Chance of Rain 30%  

Precipitation 63 mm (2.5 in)  

Rainy days 9 days  

Humidity 80% *  

Windspeed 3 m/s (6 knots) *  

Sunshine 186 hours *  

Percentage Sunshine 61% *  

* Data from: San Francisco, the United States of America (10 KM, 6 Miles).

What to Wear in San Mateo in January

The weather can be unpredictable in January, so pack clothes you can easily mix and match. You could bring jeans, other long pants, and a few t-shirts. A light jacket or light sweater will be pleasant for the cooler moments. Rain is likely on several days, so bring a good rain jacket. Expect water temperatures of around 12°C (54°F), which is definitely too cold for comfortable swimming. Your luggage space is better used for other items. Bring sunglasses since you'll have some sunny periods throughout the month

What To Do in San Mateo in January

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

5/10

Cycling

6/10

Walking

6/10

Camping

4/10

Outdoor sports

10/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our San Mateo's climate page.

More climate data for San Mateo

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full San Mateo climate overview or explore weather in the United States of America.