Livermore, CA 94550 Frost Dates
Frost dates for Livermore, CA, ZIP 94550
Typically, the last spring freeze lands around 02/15, roughly 171 days out. The first fall frost typically arrives around 12/02, about 292 frost-free days later.
The USDA Plant Hardiness Zone Map puts Livermore in Zone 9b (25 to 30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 9b around Livermore has about 14 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 02/15 isn't a guarantee
02/15 is the middle of 30 years of NOAA records, not a promise. Plant by 01/12 and you're betting against frost in roughly 9 years out of 10. 03/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Livermore compares
At roughly 292 frost-free days, Livermore places 4,320 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,676 of 2,555.
Learn more
the frost range explains how to read the range around Livermore's dates instead of trusting one, and local microclimates explains what one yard in Livermore can differ from the 94550 normal.