FrostDateCheck

Lathrop, CA 95297 Frost Dates

Frost dates for Lathrop, CA, ZIP 95297

Zone 9b

The last spring frost here typically falls around 02/06, about 162 days from today. The first fall frost typically arrives around 12/01, about 304 frost-free days later.

Lathrop 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

Zone 9b around Lathrop has about 14 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

02/06 is the middle of 30 years of NOAA records, not a promise. Plant by 02/28 and you're betting against frost in roughly 9 years out of 10. 12/31 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Lathrop compares

About 304 days separate Lathrop's last and first frost, putting it 3,760 of 40,283 ZIP codes nationally. Within CA, it ranks 1,525 of 2,555.

Learn more

zone vs. frost date explains why Zone 9b and Lathrop's frost date answer different questions, and the frost range explains how to read the range around Lathrop's dates instead of trusting one.