Island Lake, IL 60042 Frost Dates
Frost dates for Island Lake, IL, ZIP 60042
The last spring frost here typically falls around 05/01, about 246 days from today. The first fall frost typically arrives around 10/11, about 162 frost-free days later.
Zone 5b (-15 to -10°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 Island Lake, not a forecast for this year.
What to do before the first frost
Zone 5b around Island Lake has about 6 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 and you're betting against frost in roughly 9 years out of 10. 05/19 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Island Lake compares
Island Lake's growing season runs about 162 days, ranking 31,700 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 1,532 of 1,548.
Learn more
the frost range explains how to read the range around Island Lake's dates instead of trusting one, and local microclimates explains what one yard in Island Lake can differ from the 60042 normal.