Monona, WI 53788 Frost Dates
53788, near Monona, WI: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/09, roughly 161 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Monona in Zone 5b (-15 to -10°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
Monona'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 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/17 and only about 1 year in 10 sees frost after that.
Monona against the rest of the dataset
Monona's growing season runs about 161 days, ranking 32,007 of 40,283 US ZIP codes measured here, longest to shortest. Within WI, it ranks 321 of 860.
Learn more
Two guides worth reading on 53788: local microclimates, on what one yard in Monona can differ from the 53788 normal, and zone vs. frost date, on why Zone 5b and Monona's frost date answer different questions.