Knierim, IA 50552 Frost Dates
Frost dates for Knierim, IA, ZIP 50552
The last spring frost here typically falls around 04/26, about 241 days from today. The first fall frost typically arrives around 10/10, about 167 frost-free days later.
Knierim sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 5a around Knierim 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 Knierim's last frost
04/26 is the middle of 30 years of NOAA records, not a promise. Plant by 04/11 and you're betting against frost in roughly 9 years out of 10. 05/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Knierim compares
About 167 days separate Knierim's last and first frost, putting it 30,255 of 40,283 ZIP codes nationally. Within IA, it ranks 436 of 1,042.
Learn more
zone vs. frost date explains why Zone 5a and Knierim's frost date answer different questions, and the frost range explains how to read the range around Knierim's dates instead of trusting one.