Chino Hills, CA 91709 Frost Dates
Frost dates for Chino Hills, CA, ZIP 91709
The last spring frost here typically falls around 01/17, about 142 days from today. 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 Chino Hills, not a forecast for this year.
What to do before the first frost
Zone 10a around Chino Hills 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.
How much risk comes with planting early here
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 Chino Hills compares
About 335 days separate Chino Hills's last and first frost, putting it 2,738 of 40,283 ZIP codes nationally. Within CA, it ranks 1,234 of 2,555.
Learn more
the frost range explains how to read the range around Chino Hills's dates instead of trusting one, and local microclimates explains what one yard in Chino Hills can differ from the 91709 normal.