FrostDateCheck

Macomb, IL 61455 Frost Dates

Macomb, IL: when does the frost end?

Zone 6a

Around 04/17 is the usual last spring frost, about 232 days away. Fall's first freeze usually shows up around 10/22, roughly 185 days after the last spring frost.

The USDA Plant Hardiness Zone Map puts Macomb 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

With roughly 8 weeks until Macomb's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.

Why 04/17 isn't a guarantee

04/17 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 05/02 and only about 1 year in 10 sees frost after that.

Macomb against the rest of the dataset

Macomb's growing season runs about 185 days, ranking 23,083 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 827 of 1,548.

Learn more

Before leaning on 61455's figures: zone vs. frost date explains why Zone 6a and Macomb's frost date answer different questions, while the frost range explains how to read the range around Macomb's dates instead of trusting one.