Norco, CA 92880 Frost Dates
Frost dates for Norco, CA, ZIP 92880
Around 01/17 is the usual last spring frost, about 142 days away. The first fall frost typically arrives around 12/19, about 335 frost-free days later.
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 Norco, not a forecast for this year.
What to do before the first frost
Zone 10a around Norco 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.
The actual range around Norco's last frost
01/17 is the middle of 30 years of NOAA records, not a promise. Plant by 02/22 and you're betting against frost in roughly 9 years out of 10. 12/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Norco compares
At roughly 335 frost-free days, Norco places 2,744 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,240 of 2,555.
Learn more
local microclimates explains what one yard in Norco can differ from the 92880 normal, and zone vs. frost date explains why Zone 10a and Norco's frost date answer different questions.