Marion, WI 54950 Frost Dates
54950, near Marion, WI: the frost window
Around 05/04 is the usual last spring frost, about 249 days away. Fall's first freeze usually shows up around 10/06, roughly 154 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Marion in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Marion'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.
The actual range around Marion's last frost
05/04 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/22 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/19 and only about 1 year in 10 sees frost after that.
Marion against the rest of the dataset
At roughly 154 frost-free days, Marion places 34,362 of 40,283 ZIP codes in this dataset. Within WI, it ranks 492 of 860.
Learn more
Two guides worth reading on 54950: local microclimates, on what one yard in Marion can differ from the 54950 normal, and zone vs. frost date, on why Zone 5a and Marion's frost date answer different questions.