Sunnyvale, CA 94085 Frost Dates
94085, near Sunnyvale, CA: the frost window
Around 01/06 is the usual last spring frost, about 131 days away. Fall's first freeze usually shows up around 12/23, roughly 353 days after the last spring frost.
Zone 10a (30 to 35°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Sunnyvale, not a forecast for this year.
Stretching the season past the first frost
Sunnyvale'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.
Why 01/06 isn't a guarantee
01/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/16 and only about 1 year in 10 sees frost after that.
Sunnyvale against the rest of the dataset
Sunnyvale's growing season runs about 353 days, ranking 2,210 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 990 of 2,555.
Learn more
Two guides worth reading on 94085: local microclimates, on what one yard in Sunnyvale can differ from the 94085 normal, and zone vs. frost date, on why Zone 10a and Sunnyvale's frost date answer different questions.