Storm Lake, IA 50588 Frost Dates
50588, near Storm Lake, IA: the frost window
The last spring frost here typically falls around 04/30, about 245 days from today. Fall's first freeze usually shows up around 10/05, roughly 159 days after the last spring frost.
Zone 5a (-20 to -15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Storm Lake, not a forecast for this year.
Stretching the season past the first frost
Storm Lake's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Storm Lake against the rest of the dataset
Storm Lake's growing season runs about 159 days, ranking 32,618 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 776 of 1,042.
Learn more
Two guides worth reading on 50588: local microclimates, on what one yard in Storm Lake can differ from the 50588 normal, and zone vs. frost date, on why Zone 5a and Storm Lake's frost date answer different questions.