Grayling, MI 49739 Frost Dates
49739, near Grayling, MI: the frost window
Typically, the last spring freeze lands around 05/15, roughly 260 days out. Fall's first freeze usually shows up around 10/07, roughly 145 days after the last spring frost.
Grayling sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Grayling's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/15 isn't a guarantee
05/15 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/30 and only about 1 year in 10 sees frost after that.
Grayling against the rest of the dataset
At roughly 145 frost-free days, Grayling places 36,213 of 40,283 ZIP codes in this dataset. Within MI, it ranks 879 of 1,153.
Learn more
Two guides worth reading on 49739: the frost range, on how to read the range around Grayling's dates instead of trusting one, and local microclimates, on what one yard in Grayling can differ from the 49739 normal.