Fort Atkinson, IA 52144 Frost Dates
Fort Atkinson, IA: when does the frost end?
Around 05/03 is the usual last spring frost, about 248 days away. Fall's first freeze usually shows up around 10/07, roughly 157 days after the last spring frost.
Fort Atkinson 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 Fort Atkinson's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/03 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/16 and only about 1 year in 10 sees frost after that.
Fort Atkinson against the rest of the dataset
Fort Atkinson's growing season runs about 157 days, ranking 33,450 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 850 of 1,042.
Learn more
Before leaning on 52144's figures: the frost range explains how to read the range around Fort Atkinson's dates instead of trusting one, while local microclimates explains what one yard in Fort Atkinson can differ from the 52144 normal.