Isleton, CA 95680 Frost Dates
Frost dates for Isleton, CA, ZIP 95680
Typically, the last spring freeze lands around 02/09, roughly 165 days out. The first fall frost typically arrives around 12/05, about 301 frost-free days later.
The USDA Plant Hardiness Zone Map puts Isleton in Zone 9b (25 to 30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 9b around Isleton 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.
Why 02/09 isn't a guarantee
02/09 is the middle of 30 years of NOAA records, not a promise. Plant by 01/02 and you're betting against frost in roughly 9 years out of 10. 03/07 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Isleton compares
About 301 days separate Isleton's last and first frost, putting it 3,979 of 40,283 ZIP codes nationally. Within CA, it ranks 1,637 of 2,555.
Learn more
zone vs. frost date explains why Zone 9b and Isleton's frost date answer different questions, and the frost range explains how to read the range around Isleton's dates instead of trusting one.