Madison, WI 53725 Frost Dates
Madison, WI: when does the frost end?
Typically, the last spring freeze lands around 05/01, roughly 246 days out. Fall's first freeze usually shows up around 10/09, roughly 161 days after the last spring frost.
Madison sits in USDA Zone 5a (-20 to -15°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
With roughly 6 weeks until Madison's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
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.
Madison against the rest of the dataset
At roughly 161 frost-free days, Madison places 31,913 of 40,283 ZIP codes in this dataset. Within WI, it ranks 295 of 860.
Learn more
Before leaning on 53725's figures: local microclimates explains what one yard in Madison can differ from the 53725 normal, while zone vs. frost date explains why Zone 5a and Madison's frost date answer different questions.