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South San Francisco, CA weather and climate

San Mateo County, CA · population 64,487 · about 10 ft elevation

Everything below is a 30 year average for 1991-2020, computed from daily climate history at South San Francisco's own coordinates.

The year at a glance

Sunny days
248
clear or partly cloudy, per year
Precipitation
19 in
per year
Wet days
55
rain or snow per year
Snowfall
0 in
per year
Hot days
4
above 90 °F
Freezing nights
0
at or below 32 °F
Humidity
79%
average relative
Average temperature
58 °F
year round

Monthly temperatures

Average daily high and low for each month, in °F.

Daily highDaily low
506070JanMarMayJulSepNovDaily high, Jan: 58 °FDaily high, Feb: 61 °FDaily high, Mar: 63 °FDaily high, Apr: 65 °FDaily high, May: 68 °FDaily high, Jun: 71 °FDaily high, Jul: 72 °FDaily high, Aug: 73 °FDaily high, Sep: 74 °FDaily high, Oct: 72 °FDaily high, Nov: 64 °FDaily high, Dec: 58 °FDaily low, Jan: 45 °FDaily low, Feb: 46 °FDaily low, Mar: 47 °FDaily low, Apr: 49 °FDaily low, May: 51 °FDaily low, Jun: 53 °FDaily low, Jul: 55 °FDaily low, Aug: 56 °FDaily low, Sep: 56 °FDaily low, Oct: 53 °FDaily low, Nov: 49 °FDaily low, Dec: 45 °F
View monthly temperatures as a table
Monthly temperatures (°F)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Daily high586163656871727374726458
Daily low454647495153555656534945

Monthly precipitation

Total rain plus melted snow for each month, in inches.

0.02.04.0JanMarMayJulSepNovSouth San Francisco, Jan: 3.7 inSouth San Francisco, Feb: 3.8 inSouth San Francisco, Mar: 2.9 inSouth San Francisco, Apr: 1.3 inSouth San Francisco, May: 0.7 inSouth San Francisco, Jun: 0.1 inSouth San Francisco, Jul: 0.0 inSouth San Francisco, Aug: 0.0 inSouth San Francisco, Sep: 0.1 inSouth San Francisco, Oct: 0.8 inSouth San Francisco, Nov: 1.8 inSouth San Francisco, Dec: 3.4 in
View monthly precipitation as a table
Monthly precipitation (inches)
CityJanFebMarAprMayJunJulAugSepOctNovDec
South San Francisco3.73.82.91.30.70.10.00.00.10.81.83.4

Monthly sunny days

Days each month with clear or partly cloudy skies.

01020JanMarMayJulSepNovSouth San Francisco, Jan: 14 daysSouth San Francisco, Feb: 13 daysSouth San Francisco, Mar: 16 daysSouth San Francisco, Apr: 19 daysSouth San Francisco, May: 22 daysSouth San Francisco, Jun: 25 daysSouth San Francisco, Jul: 28 daysSouth San Francisco, Aug: 27 daysSouth San Francisco, Sep: 27 daysSouth San Francisco, Oct: 24 daysSouth San Francisco, Nov: 18 daysSouth San Francisco, Dec: 15 days
View monthly sunny days as a table
Monthly sunny days (days)
CityJanFebMarAprMayJunJulAugSepOctNovDec
South San Francisco141316192225282727241815

Compare South San Francisco with another city

Nearby cities and popular picks. Any two cities can be compared from the home page.

See weather for every covered California city

About this data

Figures are 30 year averages for 1991-2020. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.

Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).