Grayling, MI 49738 Frost Dates
Frost dates for Grayling, MI, ZIP 49738
Typically, the last spring freeze lands around 05/15, roughly 260 days out. The first fall frost typically arrives around 10/07, about 145 frost-free days later.
The USDA Plant Hardiness Zone Map puts Grayling in Zone 5a (-20 to -15°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 5a around Grayling has about 6 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 05/15 isn't a guarantee
05/15 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 05/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Grayling compares
At roughly 145 frost-free days, Grayling places 36,212 of 40,283 ZIP codes in this dataset. Within MI, it ranks 878 of 1,153.
Learn more
the frost range explains how to read the range around Grayling's dates instead of trusting one, and local microclimates explains what one yard in Grayling can differ from the 49738 normal.