Prairie City, IL 61470 Frost Dates
Prairie City, IL: when does the frost end?
The last spring frost here typically falls around 04/17, about 232 days from today. Fall's first freeze usually shows up around 10/22, roughly 185 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 Prairie City, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Prairie City'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.
Prairie City against the rest of the dataset
Prairie City's growing season runs about 185 days, ranking 23,301 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 841 of 1,548.
Learn more
Before leaning on 61470's figures: local microclimates explains what one yard in Prairie City can differ from the 61470 normal, while zone vs. frost date explains why Zone 6a and Prairie City's frost date answer different questions.