FrostDateCheck

Atwater, CA 95369 Frost Dates

When can you plant in Atwater, CA?

Zone 9b

Around 03/03 is the usual last spring frost, about 187 days away. The first fall frost typically arrives around 11/24, about 263 frost-free days later.

Atwater sits in USDA Zone 9b (25 to 30°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

About 13 weeks of growing season left in Atwater before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 03/03 isn't a guarantee

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

At roughly 263 frost-free days, Atwater places 6,096 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,018 of 2,555.

Learn more

local microclimates covers what one yard in Atwater can differ from the 95369 normal. zone vs. frost date covers why Zone 9b and Atwater's frost date answer different questions.