Afton, WY 83122 Frost Dates
Frost dates for Afton, WY, ZIP 83122
Typically, the last spring freeze lands around 06/20, roughly 296 days out. The first fall frost typically arrives around 09/01, about 71 frost-free days later.
The USDA Plant Hardiness Zone Map puts Afton in Zone 4b (-25 to -20°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 4b around Afton has about 1 week 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 Afton's last frost
06/20 is the middle of 30 years of NOAA records, not a promise. Plant by 06/02 and you're betting against frost in roughly 9 years out of 10. 07/07 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Afton compares
At roughly 71 frost-free days, Afton places 40,111 of 40,283 ZIP codes in this dataset. Within WY, it ranks 166 of 192.
Learn more
the frost range explains how to read the range around Afton's dates instead of trusting one, and local microclimates explains what one yard in Afton can differ from the 83122 normal.