San Ramon, CA 94516 Frost Dates
94516, near San Ramon, CA: the frost window
Typically, the last spring freeze lands around 03/08, roughly 192 days out. Fall's first freeze usually shows up around 12/22, roughly 282 days after the last spring frost.
San Ramon sits in USDA Zone 9b (25 to 30°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
San Ramon's growing season runs out in roughly 17 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around San Ramon's last frost
03/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/15 and only about 1 year in 10 sees frost after that.
San Ramon against the rest of the dataset
At roughly 282 frost-free days, San Ramon places 4,749 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,747 of 2,555.
Learn more
Two guides worth reading on 94516: local microclimates, on what one yard in San Ramon can differ from the 94516 normal, and zone vs. frost date, on why Zone 9b and San Ramon's frost date answer different questions.