Byron, MI 48816 Frost Dates
48816, near Byron, MI: the frost window
Around 05/03 is the usual last spring frost, about 248 days away. Fall's first freeze usually shows up around 10/12, roughly 161 days after the last spring frost.
Zone 6a (-10 to -5°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 Byron, not a forecast for this year.
Stretching the season past the first frost
Byron'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 05/03 isn't a guarantee
05/03 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/21 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/20 and only about 1 year in 10 sees frost after that.
Byron against the rest of the dataset
About 161 days separate Byron's last and first frost, putting it 32,132 of 40,283 ZIP codes nationally. Within MI, it ranks 599 of 1,153.
Learn more
Two guides worth reading on 48816: the frost range, on how to read the range around Byron's dates instead of trusting one, and local microclimates, on what one yard in Byron can differ from the 48816 normal.