Hayward, CA 94544 Frost Dates
Frost dates for Hayward, CA, ZIP 94544
Typically, the last spring freeze lands around 01/02, roughly 127 days out. The first fall frost typically arrives around 12/25, about 365 frost-free days later.
Zone 9b (25 to 30°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Hayward, not a forecast for this year.
What to do before the first frost
Zone 9b around Hayward has about 17 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 01/02 isn't a guarantee
01/02 is the middle of 30 years of NOAA records, not a promise. Plant by 01/27 and you're betting against frost in roughly 9 years out of 10. 12/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hayward compares
At roughly 365 frost-free days, Hayward places 389 of 40,283 ZIP codes in this dataset. Within CA, it ranks 140 of 2,555.
Learn more
zone vs. frost date explains why Zone 9b and Hayward's frost date answer different questions, and the frost range explains how to read the range around Hayward's dates instead of trusting one.