Atwater, CA 95301 Frost Dates
Frost dates for Atwater, CA, ZIP 95301
The last spring frost here typically falls around 03/03, about 187 days from today. The first fall frost typically arrives around 11/24, about 263 frost-free days later.
Atwater 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 Atwater has about 13 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
03/03 is the middle of 30 years of NOAA records, not a promise. Plant by 02/02 and you're betting against frost in roughly 9 years out of 10. 04/10 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Atwater compares
About 263 days separate Atwater's last and first frost, putting it 6,094 of 40,283 ZIP codes nationally. Within CA, it ranks 2,016 of 2,555.
Learn more
zone vs. frost date explains why Zone 9a and Atwater's frost date answer different questions, and the frost range explains how to read the range around Atwater's dates instead of trusting one.