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San Francisco County · California

San Francisco, CA weather averages

NOAA climate normals for 1991-2020, measured at San Francisco Dwtn, 0.9 km from the city centre — month by month temperature, rain and snow.

Quick answer

San Francisco averages a daily high of 63.9°F and a daily low of 50.8°F across the year, with 23.65 inches of precipitation. September is the warmest month at 70.2°F and January the coldest at 45.7°F.

Average annual high
63.9°FWarmest month September
Average annual low
50.8°FColdest month January
Precipitation per year
23.65 inWettest month December
Snowfall per year
0.1 days at or below 32°F

San Francisco weather month by month

Normal daily high and low, precipitation and snowfall for each month, 1991-2020.

MonthHigh °FLow °FPrecip inSnow inRange
January56.945.74.545.7 to 56.9 degrees
February60.247.54.4647.5 to 60.2 degrees
March61.848.53.2648.5 to 61.8 degrees
April63.149.21.4649.2 to 63.1 degrees
May64.3510.751 to 64.3 degrees
June66.452.80.1652.8 to 66.4 degrees
July66.554.154.1 to 66.5 degrees
August68.155.10.0655.1 to 68.1 degrees
September70.255.10.2155.1 to 70.2 degrees
October69.253.71.1253.7 to 69.2 degrees
November63.150.13.1650.1 to 63.1 degrees
December57.146.14.5646.1 to 57.1 degrees

Source: NOAA NCEI, U.S. Climate Normals 1991-2020 — station USW00023272, San Francisco Dwtn · rates as published for 1991-2020 normals

How to read San Francisco climate normals

What a climate normal is, and what it is not.

A normal is the average of thirty years of daily observations at one station — here San Francisco Dwtn, 0.9 km from the centre of San Francisco. It describes a typical year, so any single year will run warmer, cooler, wetter or drier. Readings taken at an airport on the edge of town usually sit a degree or two below a dense downtown on summer nights. San Francisco sees about 2.1 days a year at or above 90°F and about 45.9 days with a tenth of an inch of precipitation or more.

Other San Francisco data on this site.