Dow City, IA 51528 Frost Dates
51528, near Dow City, IA: the frost window
Around 04/27 is the usual last spring frost, about 242 days away. Fall's first freeze usually shows up around 10/11, roughly 166 days after the last spring frost.
Dow City 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
Dow City'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.
The actual range around Dow City's last frost
04/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/09 and only about 1 year in 10 sees frost after that.
Dow City against the rest of the dataset
Dow City's growing season runs about 166 days, ranking 30,432 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 470 of 1,042.
Learn more
Two guides worth reading on 51528: the frost range, on how to read the range around Dow City's dates instead of trusting one, and local microclimates, on what one yard in Dow City can differ from the 51528 normal.