Altoona, WI 54701 Frost Dates
54701, near Altoona, WI: the frost window
Around 04/24 is the usual last spring frost, about 239 days away. Fall's first freeze usually shows up around 10/14, roughly 170 days after the last spring frost.
Zone 4b (-25 to -20°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 Altoona, not a forecast for this year.
Stretching the season past the first frost
Altoona's growing season runs out in roughly 7 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/24 isn't a guarantee
04/24 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/09 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/07 and only about 1 year in 10 sees frost after that.
Altoona against the rest of the dataset
About 170 days separate Altoona's last and first frost, putting it 28,947 of 40,283 ZIP codes nationally. Within WI, it ranks 120 of 860.
Learn more
Two guides worth reading on 54701: the frost range, on how to read the range around Altoona's dates instead of trusting one, and local microclimates, on what one yard in Altoona can differ from the 54701 normal.