When is the last frost in San Francisco, CA?

Frost is extremely rare here at the nearest NOAA station (San Francisco Dwtn, CA), so there is no reliable average last frost date.

When is the first frost in San Francisco, CA?

Frost is extremely rare here at the nearest NOAA station.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 94102San Francisco, CA

Frost is extremely rare here near San Francisco, based on NOAA 1991-2020 records for the San Francisco Dwtn, CA station.

Frost is extremely rare here. Frost-tender plants can usually grow year-round, but cover them if a rare cold snap is forecast.

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	—	—	365 days	9%
Frost / freeze (32°F)	—	—	365 days	0%
Hard freeze (28°F)	—	—	365 days	0%

Where these dates come from

ZIP code 94102 is matched to the NOAA station San Francisco Dwtn, CA, 1.5 km away, at 150 ft elevation (81 ft higher than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
San Francisco Dwtn, CA (used)	150 ft	—	—
San Francisco Oceanside, CA	8 ft	Dec 30	Dec 25
Oakland Museum, CA	30 ft	—	—
Richmond, CA	20 ft	Jan 4	Jan 2

Frost dates near San Francisco

San Francisco, CA 94119 · last —, first —
Daly City, CA 94016 · last Jan 11, first Jan 10
Sausalito, CA 94966 · last Jan 4, first Jan 2
Oakland, CA 94615 · last —, first —
Brisbane, CA 94005 · last —, first —
Belvedere Tiburon, CA 94920 · last Jan 16, first Dec 18
Emeryville, CA 94662 · last —, first —
Alameda, CA 94501 · last —, first —

Frequently asked questions

When is the last frost in San Francisco, CA?: Frost is extremely rare here at the nearest NOAA station (San Francisco Dwtn, CA), so there is no reliable average last frost date.
When is the first frost in San Francisco, CA?: Frost is extremely rare here at the nearest NOAA station.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.