Atascadero, CA 93423 Frost Dates
Frost dates for Atascadero, CA, ZIP 93423
The last spring frost here typically falls around 01/19, about 144 days from today. The first fall frost typically arrives around 01/14, about 365 frost-free days later.
Atascadero sits in USDA Zone 9a (20 to 25°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 9a around Atascadero has about 20 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
01/19 is the middle of 30 years of NOAA records, not a promise. Plant by 02/09 and you're betting against frost in roughly 9 years out of 10. 12/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Atascadero compares
At roughly 365 frost-free days, Atascadero places 1,132 of 40,283 ZIP codes in this dataset. Within CA, it ranks 482 of 2,555.
Learn more
zone vs. frost date explains why Zone 9a and Atascadero's frost date answer different questions, and the frost range explains how to read the range around Atascadero's dates instead of trusting one.