Half Moon Bay, CA 94018 Frost Dates
When can you plant in Half Moon Bay, CA?
Typically, the last spring freeze lands around 02/06, roughly 162 days out. The first fall frost typically arrives around 12/17, about 328 frost-free days later.
Zone 10a (30 to 35°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 Half Moon Bay, not a forecast for this year.
What to do before the first frost
About 16 weeks of growing season left in Half Moon Bay before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Half Moon Bay's last frost
02/06 is the middle of 30 years of NOAA records, not a promise. Plant by 03/25 and you're betting against frost in roughly 9 years out of 10. 12/17 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Half Moon Bay compares
About 328 days separate Half Moon Bay's last and first frost, putting it 3,188 of 40,283 ZIP codes nationally. Within CA, it ranks 1,366 of 2,555.
Learn more
zone vs. frost date covers why Zone 10a and Half Moon Bay's frost date answer different questions. the frost range covers how to read the range around Half Moon Bay's dates instead of trusting one.