Shannon City, IA 50861 Frost Dates
50861, near Shannon City, IA: the frost window
The last spring frost here typically falls around 04/23, about 238 days from today. Fall's first freeze usually shows up around 10/17, roughly 176 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Shannon City in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Shannon City's growing season runs out in roughly 7 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 Shannon City's last frost
04/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/07 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/06 and only about 1 year in 10 sees frost after that.
Shannon City against the rest of the dataset
Shannon City's growing season runs about 176 days, ranking 26,678 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 165 of 1,042.
Learn more
Two guides worth reading on 50861: zone vs. frost date, on why Zone 5b and Shannon City's frost date answer different questions, and the frost range, on how to read the range around Shannon City's dates instead of trusting one.