FrostDateCheck

Union, KY 41091 Frost Dates

Frost dates for Union, KY, ZIP 41091

Zone 6b

Typically, the last spring freeze lands around 04/18, roughly 233 days out. The first fall frost typically arrives around 10/25, about 188 frost-free days later.

Union sits in USDA Zone 6b (-5 to 0°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 6b around Union has about 8 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

04/18 is the middle of 30 years of NOAA records, not a promise. Plant by 04/03 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 Union compares

About 188 days separate Union's last and first frost, putting it 21,956 of 40,283 ZIP codes nationally. Within KY, it ranks 597 of 909.

Learn more

zone vs. frost date explains why Zone 6b and Union's frost date answer different questions, and the frost range explains how to read the range around Union's dates instead of trusting one.