Waterloo, IL 62298 Frost Dates
62298, near Waterloo, IL: the frost window
Typically, the last spring freeze lands around 04/09, roughly 224 days out. Fall's first freeze usually shows up around 10/26, roughly 197 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Waterloo in Zone 7a (0 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
Waterloo'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.
The actual range around Waterloo's last frost
04/09 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/25 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/25 and only about 1 year in 10 sees frost after that.
Waterloo against the rest of the dataset
At roughly 197 frost-free days, Waterloo places 18,647 of 40,283 ZIP codes in this dataset. Within IL, it ranks 315 of 1,548.
Learn more
Two guides worth reading on 62298: zone vs. frost date, on why Zone 7a and Waterloo's frost date answer different questions, and the frost range, on how to read the range around Waterloo's dates instead of trusting one.