FrostDateCheck

Elk Mountain, WY 82055 Frost Dates

When can you plant in Elk Mountain, WY?

Zone 5a

Typically, the last spring freeze lands around 06/02, roughly 278 days out. The first fall frost typically arrives around 09/15, about 102 frost-free days later.

Elk Mountain 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

About 3 weeks of growing season left in Elk Mountain before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 06/02 isn't a guarantee

06/02 is the middle of 30 years of NOAA records, not a promise. Plant by 05/21 and you're betting against frost in roughly 9 years out of 10. 06/18 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Elk Mountain compares

At roughly 102 frost-free days, Elk Mountain places 39,674 of 40,283 ZIP codes in this dataset. Within WY, it ranks 140 of 192.

Learn more

local microclimates covers what one yard in Elk Mountain can differ from the 82055 normal. zone vs. frost date covers why Zone 5a and Elk Mountain's frost date answer different questions.