McGregor, IA 52157 Frost Dates
Frost dates for McGregor, IA, ZIP 52157
Around 04/28 is the usual last spring frost, about 243 days away. The first fall frost typically arrives around 10/12, about 166 frost-free days later.
The USDA Plant Hardiness Zone Map puts McGregor in Zone 5a (-20 to -15°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 5a around McGregor 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.
The actual range around McGregor's last frost
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/14 and you're betting against frost in roughly 9 years out of 10. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How McGregor compares
About 166 days separate McGregor's last and first frost, putting it 30,423 of 40,283 ZIP codes nationally. Within IA, it ranks 467 of 1,042.
Learn more
zone vs. frost date explains why Zone 5a and McGregor's frost date answer different questions, and the frost range explains how to read the range around McGregor's dates instead of trusting one.