Granite City, IL 62040 Frost Dates
62040, near Granite City, IL: the frost window
Around 04/04 is the usual last spring frost, about 219 days away. Fall's first freeze usually shows up around 11/05, roughly 214 days after the last spring frost.
Granite City sits in USDA Zone 7a (0 to 5°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Granite City's growing season runs out in roughly 10 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/04 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/19 and only about 1 year in 10 sees frost after that.
Granite City against the rest of the dataset
Granite City's growing season runs about 214 days, ranking 14,227 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 7 of 1,548.
Learn more
Two guides worth reading on 62040: the frost range, on how to read the range around Granite City's dates instead of trusting one, and local microclimates, on what one yard in Granite City can differ from the 62040 normal.