Spencer, WI 54479 Frost Dates
54479, near Spencer, WI: the frost window
Typically, the last spring freeze lands around 05/05, roughly 250 days out. Fall's first freeze usually shows up around 10/05, roughly 152 days after the last spring frost.
Spencer sits in USDA Zone 4b (-25 to -20°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Spencer'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.
The actual range around Spencer's last frost
05/05 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 05/20 and only about 1 year in 10 sees frost after that.
Spencer against the rest of the dataset
Spencer's growing season runs about 152 days, ranking 34,788 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 521 of 860.
Learn more
Two guides worth reading on 54479: local microclimates, on what one yard in Spencer can differ from the 54479 normal, and zone vs. frost date, on why Zone 4b and Spencer's frost date answer different questions.