Concord, IL 62631 Frost Dates
62631, near Concord, IL: the frost window
Around 04/19 is the usual last spring frost, about 234 days away. Fall's first freeze usually shows up around 10/17, roughly 179 days after the last spring frost.
Zone 6a (-10 to -5°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 Concord, not a forecast for this year.
Stretching the season past the first frost
Concord'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.
Why 04/19 isn't a guarantee
04/19 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 05/05 and only about 1 year in 10 sees frost after that.
Concord against the rest of the dataset
About 179 days separate Concord's last and first frost, putting it 25,514 of 40,283 ZIP codes nationally. Within IL, it ranks 1,073 of 1,548.
Learn more
Two guides worth reading on 62631: zone vs. frost date, on why Zone 6a and Concord's frost date answer different questions, and the frost range, on how to read the range around Concord's dates instead of trusting one.