Carter Lake, IA 68110 Frost Dates
68110, near Carter Lake, IA: the frost window
Around 04/18 is the usual last spring frost, about 233 days away. Fall's first freeze usually shows up around 10/21, roughly 185 days after the last spring frost.
Carter Lake sits in USDA Zone 6a (-10 to -5°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
Carter Lake's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/18 isn't a guarantee
04/18 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/30 and only about 1 year in 10 sees frost after that.
Carter Lake against the rest of the dataset
About 185 days separate Carter Lake's last and first frost, putting it 23,154 of 40,283 ZIP codes nationally. Within IA, it ranks 39 of 1,042.
Learn more
Two guides worth reading on 68110: local microclimates, on what one yard in Carter Lake can differ from the 68110 normal, and zone vs. frost date, on why Zone 6a and Carter Lake's frost date answer different questions.