Marquette, MI 49885 Frost Dates
Frost dates for Marquette, MI, ZIP 49885
The last spring frost here typically falls around 05/13, about 258 days from today. The first fall frost typically arrives around 10/02, about 141 frost-free days later.
Zone 5a (-20 to -15°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 Marquette, not a forecast for this year.
What to do before the first frost
Zone 5a around Marquette has about 5 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 05/13 isn't a guarantee
05/13 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. 05/29 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Marquette compares
About 141 days separate Marquette's last and first frost, putting it 36,867 of 40,283 ZIP codes nationally. Within MI, it ranks 906 of 1,153.
Learn more
zone vs. frost date explains why Zone 5a and Marquette's frost date answer different questions, and the frost range explains how to read the range around Marquette's dates instead of trusting one.