Mount Morris, IL 61054 Frost Dates
61054, near Mount Morris, IL: the frost window
Typically, the last spring freeze lands around 04/26, roughly 241 days out. Fall's first freeze usually shows up around 10/13, roughly 169 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Mount Morris in Zone 5b (-15 to -10°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
Mount Morris'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.
How much risk comes with planting early here
04/26 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Mount Morris against the rest of the dataset
At roughly 169 frost-free days, Mount Morris places 29,451 of 40,283 ZIP codes in this dataset. Within IL, it ranks 1,424 of 1,548.
Learn more
Two guides worth reading on 61054: the frost range, on how to read the range around Mount Morris's dates instead of trusting one, and local microclimates, on what one yard in Mount Morris can differ from the 61054 normal.