South San Francisco, CA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for South San Francisco, a city in San Mateo County, California.

Overnight

57°F

Partly Cloudy

Partly cloudy, with a low around 57. West southwest wind around 3 mph.

7-day forecast for South San Francisco

When	Temp	Forecast	Wind	Precip
Overnight	57°F	Partly Cloudy	3 mph WSW	0%
Tuesday	78°F	Haze then Sunny	2 to 12 mph W	1%
Tuesday Night	58°F	Mostly Clear	2 to 10 mph WSW	1%
Wednesday	78°F	Sunny	2 to 10 mph WSW	0%
Wednesday Night	58°F	Partly Cloudy	1 to 10 mph WSW	0%
Thursday	77°F	Mostly Sunny	1 to 12 mph WSW	0%
Thursday Night	59°F	Partly Cloudy	2 to 12 mph W	0%
Friday	79°F	Sunny	2 to 12 mph W	0%
Friday Night	60°F	Partly Cloudy	5 to 12 mph WSW	0%
Saturday	72°F	Sunny	3 to 12 mph WSW	0%
Saturday Night	61°F	Mostly Clear	12 mph WSW	0%
Sunday	69°F	Sunny	8 to 15 mph WSW	0%
Sunday Night	59°F	Mostly Clear	12 to 15 mph WSW	0%
Monday	67°F	Mostly Sunny	10 to 15 mph WSW	0%

Forecast source: National Weather Service (api.weather.gov) for South San Francisco (37.655, -122.376). Updated through the day.

Growing snapshot for South San Francisco

Last spring frost

Dec 29

First fall frost

Dec 26

Growing season

365 days

Hardiness zone

10a

More local growing data for South San Francisco: nearby ZIP 94128 weather · frost dates · planting calendar · California frost dates

Nearby towns & communities

Atherton Baywood Park Belmont Brisbane Broadmoor Burlingame Colma Daly City El Granada Emerald Lake Hills Foster City Half Moon Bay Highlands Hillsborough La Honda Ladera Loma Mar Millbrae Montara Moss Beach North Fair Oaks Pacifica Pescadero Portola Valley Redwood City San Bruno San Carlos San Mateo West Menlo Park Woodside

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Climate data from the nearest NOAA station, San Francisco Intl Ap, Ca (1.1 mi from South San Francisco). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.