January Weather in San Francisco, Mexico

Last updated: August 27, 2025

In January, the average temperature in San Francisco, Mexico is a pleasant 23°C (73°F). Expect lows of 10°C (51°F) and highs that can reach 33°C (92°F). 🌦️ With an average precipitation of 38 mm (1.5 in) over 7 days, and humidity levels around 81%, it’s a month that balances warmth with a hint of moisture.

January Temperature in San Francisco

In January in San Francisco, the average temperature is 23°C (73°F). The maximum can reach 33°C (92°F), and the minimum can be as low as 10°C (51°F). Overall, it's a great time to visit San Francisco, with warm days and cooler nights making it ideal for outdoor adventures.

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 23°C (73°F), with highs reaching up to 33°C (92°F) and lows dropping to around 10°C (51°F).

Data source: Temperature data for San Francisco generated using information from the Copernicus Climate Change Service.

January Precipitation in San Francisco

In San Francisco in January, the precipitation amount is 38 mm (1.5 in) over the course of 7 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 38 mm (1.5 inches) of precipitation spread over approximately 7 days.

Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in San Francisco

In San Francisco in January, humidity is 81%. With an average temperature of 23°C (73°F), this humidity feels like a heavy blanket wrapping around you, making every step feel more laborious while traveling and causing you to constantly seek out shade or a cool breeze for relief.

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 81%, offering insight into how humid the weather typically is during this month.

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.

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.
	Temperature	Precipitation	Humidity	UV
January Weather	23°C (73°F)	38 mm (1.5 inches)	81%	very high
February Weather	24°C (76°F)	19 mm (0.8 inches)	78%	very high
March Weather	25°C (77°F)	15 mm (0.6 inches)	71%	extreme
April Weather	27°C (81°F)	38 mm (1.5 inches)	70%	extreme
May Weather	28°C (82°F)	89 mm (3.5 inches)	68%	extreme
June Weather	28°C (82°F)	164 mm (6.5 inches)	69%	extreme
July Weather	28°C (83°F)	87 mm (3.4 inches)	74%	extreme
August Weather	28°C (83°F)	110 mm (4.3 inches)	81%	extreme
September Weather	27°C (82°F)	148 mm (5.8 inches)	82%	extreme
October Weather	26°C (80°F)	174 mm (6.9 inches)	83%	extreme
November Weather	24°C (76°F)	67 mm (2.6 inches)	84%	very high
December Weather	23°C (74°F)	35 mm (1.4 inches)	86%	high