Afton, WY 83111 Frost Dates
When can you plant in Afton, WY?
The last spring frost here typically falls around 06/20, about 296 days from today. 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
About 1 week of growing season left in Afton before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
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 40,109 of 40,283 ZIP codes in this dataset. Within WY, it ranks 164 of 192.
Learn more
zone vs. frost date covers why Zone 4b and Afton's frost date answer different questions. the frost range covers how to read the range around Afton's dates instead of trusting one.