Marine City, MI 48039 Frost Dates
Frost dates for Marine City, MI, ZIP 48039
Around 05/03 is the usual last spring frost, about 248 days away. The first fall frost typically arrives around 10/18, about 167 frost-free days later.
Zone 6b (-5 to 0°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 Marine City, not a forecast for this year.
What to do before the first frost
Zone 6b around Marine City has about 7 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 Marine City's last frost
05/03 is the middle of 30 years of NOAA records, not a promise. Plant by 04/20 and you're betting against frost in roughly 9 years out of 10. 05/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Marine City compares
About 167 days separate Marine City's last and first frost, putting it 29,973 of 40,283 ZIP codes nationally. Within MI, it ranks 366 of 1,153.
Learn more
local microclimates explains what one yard in Marine City can differ from the 48039 normal, and zone vs. frost date explains why Zone 6b and Marine City's frost date answer different questions.