Fairfax, CA 94950 Frost Dates
Frost dates for Fairfax, CA, ZIP 94950
Around 01/11 is the usual last spring frost, about 136 days away. The first fall frost typically arrives around 12/21, about 349 frost-free days later.
The USDA Plant Hardiness Zone Map puts Fairfax 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 Fairfax has about 16 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 01/11 isn't a guarantee
01/11 is the middle of 30 years of NOAA records, not a promise. Plant by 02/25 and you're betting against frost in roughly 9 years out of 10. 12/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Fairfax compares
About 349 days separate Fairfax's last and first frost, putting it 2,354 of 40,283 ZIP codes nationally. Within CA, it ranks 1,060 of 2,555.
Learn more
local microclimates explains what one yard in Fairfax can differ from the 94950 normal, and zone vs. frost date explains why Zone 9b and Fairfax's frost date answer different questions.