FrostDateByZip

Frost dates for 95120San Jose, CA

The average last spring frost in San Jose is February 2 and the average first fall frost is December 6, giving a typical growing season of about 310 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Feb 2

Safer after Mar 14 (1-in-10 risk)

Average first fall frost
Dec 6

Possible by Nov 16 (1-in-10 risk)

Growing season
310 days

First frost typically in 35 days

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.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)Feb 16 · Mar 20 · Apr 16Nov 4 · Nov 20 · Dec 5241 days100%
Frost / freeze (32°F)Dec 31 · Feb 2 · Mar 14Nov 16 · Dec 6 · Jan 7310 days97%
Hard freeze (28°F)Dec 9 · Jan 1 · Jan 26Nov 28 · Dec 19 · Jan 13356 days58%

Where these dates come from

ZIP code 95120 is matched to the NOAA station Los Gatos, CA, 9.2 km away, at 365 ft elevation (93 ft higher than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Los Gatos, CA (used)365 ftFeb 2Dec 6
San Jose, CA67 ftJan 2Dec 25
San Jose, CA51 ftJan 12Dec 22
Mt Hamilton, CA4,206 ftMay 3Nov 18

Frost dates near San Jose

Frequently asked questions

When is the last frost in San Jose, CA?
For ZIP code 95120, the average last spring frost (32°F) is February 2, based on NOAA 1991-2020 climate normals for the Los Gatos, CA weather station. There is a 1-in-10 chance of a frost after March 14.
When is the first frost in San Jose, CA?
The average first fall frost (32°F) is December 6. There is a 1-in-10 chance of frost by November 16, so tender plants are at risk from that point on.
How long is the growing season in 95120?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 310 days long.
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.