Mount Ayr, IN 47943 Frost Dates
Frost dates for Mount Ayr, IN, ZIP 47943
Typically, the last spring freeze lands around 04/23, roughly 238 days out. The first fall frost typically arrives around 10/18, about 177 frost-free days later.
The USDA Plant Hardiness Zone Map puts Mount Ayr 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 Mount Ayr 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.
How much risk comes with planting early here
04/23 is the middle of 30 years of NOAA records, not a promise. Plant by 04/09 and you're betting against frost in roughly 9 years out of 10. 05/07 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Mount Ayr compares
Mount Ayr's growing season runs about 177 days, ranking 26,299 of 40,283 US ZIP codes measured here, longest to shortest. Within IN, it ranks 616 of 927.
Learn more
zone vs. frost date explains why Zone 5b and Mount Ayr's frost date answer different questions, and the frost range explains how to read the range around Mount Ayr's dates instead of trusting one.