Waukesha, WI 53186 Frost Dates
Frost dates for Waukesha, WI, ZIP 53186
Around 05/01 is the usual last spring frost, about 246 days away. The first fall frost typically arrives around 10/13, 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 Waukesha, not a forecast for this year.
What to do before the first frost
Zone 5b around Waukesha has about 7 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 04/18 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Waukesha compares
At roughly 162 frost-free days, Waukesha places 31,591 of 40,283 ZIP codes in this dataset. Within WI, it ranks 246 of 860.
Learn more
zone vs. frost date explains why Zone 5b and Waukesha's frost date answer different questions, and the frost range explains how to read the range around Waukesha's dates instead of trusting one.