Montour, IA 50173 Frost Dates
Frost dates for Montour, IA, ZIP 50173
The last spring frost here typically falls around 04/30, about 245 days from today. The first fall frost typically arrives around 10/09, about 162 frost-free days later.
The USDA Plant Hardiness Zone Map puts Montour 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 Montour 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
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 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 Montour compares
About 162 days separate Montour's last and first frost, putting it 31,876 of 40,283 ZIP codes nationally. Within IA, it ranks 734 of 1,042.
Learn more
local microclimates explains what one yard in Montour can differ from the 50173 normal, and zone vs. frost date explains why Zone 5a and Montour's frost date answer different questions.