Union Grove, WI 53182 Frost Dates
Frost dates for Union Grove, WI, ZIP 53182
The last spring frost here typically falls around 05/05, about 250 days from today. The first fall frost typically arrives around 10/08, about 156 frost-free days later.
The USDA Plant Hardiness Zone Map puts Union Grove in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 5b around Union Grove 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.
How much risk comes with planting early here
05/05 is the middle of 30 years of NOAA records, not a promise. Plant by 04/21 and you're betting against frost in roughly 9 years out of 10. 05/20 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Union Grove compares
At roughly 156 frost-free days, Union Grove places 33,573 of 40,283 ZIP codes in this dataset. Within WI, it ranks 416 of 860.
Learn more
local microclimates explains what one yard in Union Grove can differ from the 53182 normal, and zone vs. frost date explains why Zone 5b and Union Grove's frost date answer different questions.