Climateby Month

San Francisco, CA weather in January

NOAA 1991-2020 normals and daily records · San Francisco all year

San Francisco is cool in January, with frequent rain: highs average 58°F and nights drop to about 47°F. Rain falls on about 11 days. It is one of the coolest months in San Francisco.

Normal high
58°F
Normal low
47°F
Wet days
11
4.4 in total
Muggy days
0
dew point 65°F+

How January changes from start to finish

Normal values at the start and end of January
January 1January 31
Normal high57°F59°F
Normal low46°F47°F
Chance of a wet day37%35%
Sunrise / sunset7:25 am / 5:01 pm7:14 am / 5:31 pm
Daylight9.6 h10.3 h

Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Pacific Time).

A typical January day

  1. 6 am47°Fdew point 43°F
  2. 9 am50°Fdew point 44°F
  3. Noon53°Fdew point 45°F
  4. 3 pm55°Fdew point 45°F
  5. 6 pm53°Fdew point 45°F
  6. 9 pm51°Fdew point 45°F

NOAA hourly normals (local standard time) from San Francisco Intl Airport (11 mi away); average wind 7 mph; clear or few clouds in 29% of daytime hours, mostly cloudy or overcast in 57%.

What kind of days to expect

  • Comfortable dayshigh 65-80°F and dew point under 60°F4 of 31
  • Beach dayshigh 80-95°F, under 0.05 in of rain, afternoon wind under 15 mph0 of 31
  • Hot dayshigh 90°F or more0 of 31
  • Muggy daysdaily mean dew point 65°F or more0 of 31
  • Wet daysat least 0.01 in of rain or melted snow11 of 31
  • Notable rainat least 0.10 in8 of 31
  • Freezing nightslow 32°F or below0 of 31

Average days per January, counted from daily records for each year 1991-2020.

Rain in January

Normal precipitation is 4.4 in; a dry January brings about 1.8 in and a wet one about 6.7 in (25th and 75th percentiles). About 3 days bring half an inch or more, and about 1 an inch or more.

How January varies from year to year

  • Warmest January, 1991-20202014: average high 64°F
  • Coolest January2008: average high 55°F
  • Wettest January1998: 12.1 in
  • Driest January2015: no measurable precipitation
  • Highest reading74°F (January 31, 2015)
  • Lowest reading36°F (January 28, 2002)

From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.

January compared with December and February

DecemberJanuaryFebruary
Normal high58°F58°F60°F
Normal low47°F47°F48°F
Wet days121111
Comfortable days347
Daylight9.6 h9.9 h10.8 h

Highs change by 0°F from December and +2°F into February.

Nearby alternatives in January

How San Francisco ranks in January

  • Normal high131st warmest of 378 cities; 45th of 60 in California
  • Wet days282nd driest of 378
  • Comfortable days143rd most of 339

What to pack for San Francisco in January

  • A rain jacket or umbrella – rain on about 11 days

Heating and cooling

January has 397 heating degree days and 0 cooling degree days (base 65°F), 14% of the year's total heating and cooling demand.

Questions

How cold is San Francisco in January?

The normal high is 58°F and the normal low is 47°F. From 1991 to 2020 the coldest January reading was 36°F (most recently on January 28, 2002).

Does it rain a lot in San Francisco in January?

About 11 days in January have at least 0.01 in of precipitation, and the normal total is 4.4 in. The wettest January in 1991-2020 was in 1998 (12.1 in); the driest was in 2015, with no measurable precipitation.

Is January a good time to visit San Francisco?

January ranks 11th of 12 months on our comfort score for San Francisco (46 out of 100). It has about 4 comfortable days. The best months are July and August.

Where the numbers come from

  • Temperature, rain and frost dates: San Francisco Downtown (USW00023272), 0.5 mi SW of the city center, 150 ft (95 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Snowfall and snow depth: San Francisco Oceanside (USC00047767), 5.7 mi SW of the city center, 8 ft . NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour and cloud cover: San Francisco Intl Airport (USW00023234), 11 mi SSE of the city center, 8 ft . NOAA normals and daily records, 1991-2020.
  • Daily humidity and wind: San Francisco International Airport (724940-23234), 11 mi SSE of the city center, 10 ft . Hourly observations, 1991-2020.