Mammoth Lakes, CA 95389 Frost Dates
Frost dates for Mammoth Lakes, CA, ZIP 95389
Typically, the last spring freeze lands around 05/12, roughly 257 days out. The first fall frost typically arrives around 11/01, about 171 frost-free days later.
The USDA Plant Hardiness Zone Map puts Mammoth Lakes in Zone 7a (0 to 5°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 7a around Mammoth Lakes has about 9 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.
The actual range around Mammoth Lakes's last frost
05/12 is the middle of 30 years of NOAA records, not a promise. Plant by 04/18 and you're betting against frost in roughly 9 years out of 10. 06/04 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Mammoth Lakes compares
At roughly 171 frost-free days, Mammoth Lakes places 28,618 of 40,283 ZIP codes in this dataset. Within CA, it ranks 2,379 of 2,555.
Learn more
local microclimates explains what one yard in Mammoth Lakes can differ from the 95389 normal, and zone vs. frost date explains why Zone 7a and Mammoth Lakes's frost date answer different questions.