Prospect Heights, IL 60070 Frost Dates
60070, near Prospect Heights, IL: the frost window
The last spring frost here typically falls around 04/19, about 234 days from today. Fall's first freeze usually shows up around 10/26, roughly 190 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Prospect Heights in Zone 6a (-10 to -5°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
Prospect Heights'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.
How much risk comes with planting early here
04/19 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/03 and only about 1 year in 10 sees frost after that.
Prospect Heights against the rest of the dataset
About 190 days separate Prospect Heights's last and first frost, putting it 21,070 of 40,283 ZIP codes nationally. Within IL, it ranks 502 of 1,548.
Learn more
Two guides worth reading on 60070: the frost range, on how to read the range around Prospect Heights's dates instead of trusting one, and local microclimates, on what one yard in Prospect Heights can differ from the 60070 normal.