Cheyenne, WY 82002 Frost Dates
Cheyenne, WY: when does the frost end?
Typically, the last spring freeze lands around 05/12, roughly 257 days out. Fall's first freeze usually shows up around 10/01, roughly 141 days after the last spring frost.
Cheyenne sits in USDA Zone 5b (-15 to -10°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.
Stretching the season past the first frost
With roughly 5 weeks until Cheyenne's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/12 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/01 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/26 and only about 1 year in 10 sees frost after that.
Cheyenne against the rest of the dataset
At roughly 141 frost-free days, Cheyenne places 36,860 of 40,283 ZIP codes in this dataset. Within WY, it ranks 23 of 192.
Learn more
Before leaning on 82002's figures: local microclimates explains what one yard in Cheyenne can differ from the 82002 normal, while zone vs. frost date explains why Zone 5b and Cheyenne's frost date answer different questions.