Copper City, MI 49942 Frost Dates
49942, near Copper City, MI: the frost window
The last spring frost here typically falls around 05/17, about 262 days from today. Fall's first freeze usually shows up around 10/01, roughly 138 days after the last spring frost.
Zone 5b (-15 to -10°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 Copper City, not a forecast for this year.
Stretching the season past the first frost
Copper City's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/17 isn't a guarantee
05/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/01 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/03 and only about 1 year in 10 sees frost after that.
Copper City against the rest of the dataset
Copper City's growing season runs about 138 days, ranking 37,460 of 40,283 US ZIP codes measured here, longest to shortest. Within MI, it ranks 935 of 1,153.
Learn more
Two guides worth reading on 49942: the frost range, on how to read the range around Copper City's dates instead of trusting one, and local microclimates, on what one yard in Copper City can differ from the 49942 normal.