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January Weather in San Francisco, Mexico

Last updated: August 27, 2025

In January, the average temperature in San Francisco, Mexico hovers around a pleasant 17°C (63°F). Expect a minimum chill of 6°C (43°F) and a warm peak at 31°C (89°F). With 92 mm (3.6 in) of precipitation spread over 14 days, remember your umbrella. The air can feel quite humid, with an average humidity of 88%, adding a touch of tropical warmth to your experience!

January Temperature in San Francisco

In January in San Francisco, the average temperature is 17°C (63°F). Maximum temperatures can reach 31°C (89°F), while minimums can drop to as low as 6°C (43°F). Be prepared for a range of temperatures if you're planning to travel during this time.

January Weather in San Francisco: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in San Francisco, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Francisco, January typically has an average temperature of 17°C (63°F), with highs reaching up to 31°C (89°F) and lows dropping to around 6°C (43°F).
JanFebMarAprMayJunJulAugSepOctNovDec636669747878777777736864
Data source: Temperature data for San Francisco generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

January Precipitation in San Francisco

In San Francisco in January, the precipitation amount is 92 mm (3.6 in) over the course of 14 days.

January Precipitation Trends in San Francisco

The chart displays monthly precipitation patterns in San Francisco, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In San Francisco, January typically receives around 92 mm (3.6 inches) of precipitation spread over approximately 14 days.
JanFebMarAprMayJunJulAugSepOctNovDec927911211718521114119121228712762
Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.
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January Humidity in San Francisco

In San Francisco in January, humidity is 88%. With an average temperature of 17°C (63°F), this humidity feels like a thick blanket enveloping you, making outdoor activities feel stifling and sticky, potentially dampening the joy of exploration and requiring frequent breaks for hydration.

January Average Humidity in San Francisco

This chart illustrates the average monthly humidity levels in San Francisco, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in San Francisco is approximately 88%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%86%83%80%82%79%72%74%84%92%91%91%
Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in San Francisco

In San Francisco in January, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in San Francisco.

Maximum UV Index Levels in San Francisco for January

The chart shows the monthly maximum UV Index (UVI) for San Francisco in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in San Francisco typically reaches 8, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec811121313131313131197
Data source: San Francisco January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How January Weather in San Francisco Compares to Other Months

Weather in San Francisco varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in San Francisco, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Francisco, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather17°C (63°F)92 mm (3.6 inches)88%very high
February Weather19°C (66°F)79 mm (3.1 inches)86%extreme
March Weather21°C (70°F)112 mm (4.4 inches)83%extreme
April Weather23°C (74°F)117 mm (4.6 inches)80%extreme
May Weather25°C (78°F)185 mm (7.3 inches)82%extreme
June Weather25°C (78°F)210 mm (8.3 inches)79%extreme
July Weather25°C (77°F)141 mm (5.5 inches)72%extreme
August Weather25°C (78°F)191 mm (7.5 inches)74%extreme
September Weather25°C (77°F)212 mm (8.4 inches)84%extreme
October Weather23°C (74°F)287 mm (11.3 inches)92%extreme
November Weather20°C (68°F)127 mm (5.0 inches)91%very high
December Weather18°C (64°F)62 mm (2.4 inches)91%high

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