Sault Ste. Marie, MI 49710 Frost Dates
Frost dates for Sault Ste. Marie, MI, ZIP 49710
Typically, the last spring freeze lands around 05/31, roughly 276 days out. The first fall frost typically arrives around 09/25, about 116 frost-free days later.
Sault Ste. Marie sits in USDA Zone 4b (-25 to -20°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.
What to do before the first frost
Zone 4b around Sault Ste. Marie has about 4 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.
How much risk comes with planting early here
05/31 is the middle of 30 years of NOAA records, not a promise. Plant by 05/14 and you're betting against frost in roughly 9 years out of 10. 06/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Sault Ste. Marie compares
At roughly 116 frost-free days, Sault Ste. Marie places 39,274 of 40,283 ZIP codes in this dataset. Within MI, it ranks 1,117 of 1,153.
Learn more
the frost range explains how to read the range around Sault Ste. Marie's dates instead of trusting one, and local microclimates explains what one yard in Sault Ste. Marie can differ from the 49710 normal.