This post summarizes the San Francisco weather in January, with tips on how to dress and things to do.
You may find our posts for the weather in December and February also helpful.
AVERAGE JANUARY TEMPERATURES
San Francisco during January tends to be on the cool side, but quite mild when compared to most of the rest of the United States during mid-winter.
Daytime highs tend to be in the mid-50s F (13-14 C) as the new year begins, warming into the upper 50s F (15 C) by month’s end.

A few of the warmer days, especially near the end of the month will, sometimes, reach or exceed 65 F (18 C).
Overnight lows tend to average in the mid-40s F (7-8 C) with a couple of the colder mornings dipping down into the upper 30s F (3-4 C).
The warmest temperature ever reported in January was 79 F (26.1 C) while the coldest was 30 F (-1.1 C).
HOW MUCH SUN AND RAIN?
Skies over San Francisco during January tend to be sunny or at least partly sunny on about 16 days with cloudy or mostly cloudy conditions on 15 days.
Some rainfall occurs on about 11 days this month; however, rainfalls of at least 0.04 inches (1 mm) occur on about 8 days.
Heavy rains of ½ inch (13 mm) or more occur only on about 3 days during this month.

Wind speed average around 8-9 mph (13-14 kph) during January, ranging mostly between 4mph and 15 mph (6-24 kph).
Daylight increases during the course of the month from a little over 9 and a half hours on New Year‘s Day to over 10 hours by month’s end.
WHAT TO WEAR IN SAN FRANCISCO IN JANUARY
So, what should you pack for a January visit to San Francisco?
We recommend bringing a sweater or sweatshirt in addition to a light to medium weight jacket to wear while exploring the city.

On the colder and windier days, it will be helpful to have multiple warm layers in addition to the jacket.
The wind near the waterfront tends to be somewhat stronger so dress accordingly and remember to bring a good pair of walking shoes.
THINGS TO DO IN JANUARY
There are more things to do in January than we can list here, so be sure to read our full post on what to do and see this month, as well as our master post for any time of the year.
And if you are planning on visiting many of San Francisco's top attractions, then you should consider a tourist discount pass.
These passes could save you up to 50% of retail ticket prices to tours, attractions, and restaurants.
- Take a pay-what-you-like walking tour.
- See a major artist in concert.
- Go to a professional basketball or hockey game.
- Enjoy a traveling Broadway musical.
- Join in the Hot Chocolate 15k or 5k.
- Celebrate Martin Luther King Jr. Day with free activities.
- Celebrate the Chinese New Year at the Flower Market Fair.
- Explore the city's Redwood Grove.
Seasonal Outlook - January to March 2023 San Francisco
Temperatures are expected to be near normal with a 77% chance for below normal rainfall.
Written by Fred Pickhardt