Burnt Prairie, IL 62820 Frost Dates
Burnt Prairie, IL: when does the frost end?
Around 04/15 is the usual last spring frost, about 230 days away. Fall's first freeze usually shows up around 10/19, roughly 183 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Burnt Prairie in Zone 6b (-5 to 0°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 7 weeks until Burnt Prairie's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/15 isn't a guarantee
04/15 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/02 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.
Burnt Prairie against the rest of the dataset
At roughly 183 frost-free days, Burnt Prairie places 24,050 of 40,283 ZIP codes in this dataset. Within IL, it ranks 895 of 1,548.
Learn more
Before leaning on 62820's figures: local microclimates explains what one yard in Burnt Prairie can differ from the 62820 normal, while zone vs. frost date explains why Zone 6b and Burnt Prairie's frost date answer different questions.