Frost Dates for 82414 — Cody, Wyoming

Half of springs at Buffalo Bill Dam, WY see their last 32°F night by May 17; only one in ten is past it by May 1, and one in ten still has one after June 3. Planting tender crops after May 25 leaves a 30% risk of a frost on them, after May 30 20%, and after June 3 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 73% of the 33 Wyoming stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 3 in half of years, as early as September 18 one year in ten, and holds off past October 17 one year in ten. A hard freeze of 28°F follows 9 days later, around October 12; in spring the one-in-ten date for 28°F is May 25, 9 days before the 32°F one. The freeze-free season lasts 136 days in a typical year, longer than at 70% of the 33 Wyoming stations; it reaches 157 days one year in ten and falls short of 113 one year in ten. On average 140 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 13 days longer, to about May 30, and return around September 23. Severe cold of 16°F or below comes every winter, usually between November 7 and March 25.

July is the warmest month at Buffalo Bill Dam, WY, averaging 82°F by day and 57°F at night; December is the coldest at 35°F and 19°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 89% of years and June still brings one in 16% of years.

Warmth for growing adds up to 2,012 growing degree days a year (base 50°F), fewer than at 58% of the 33 Wyoming stations. 24% of them (481) have built up by the end of June, and July adds the most, 598. Precipitation totals 12.8 inches a year, most in May (3.2") and least in January (0.4"); May to September bring 59% of it.

The nearest other station, Powell Field Stn, WY, 26 miles northeast of Cody and 788 feet lower, has a last frost 2 days later (May 19), a first frost 13 days earlier (September 20), a season 13 days shorter.

The first measurable snow (0.1 inch or more) in Cody usually arrives around October 22, and the last of the season around April 19. Those are the middle dates across the winters of 1991–2020 at Cody, WY, 6.5 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 28 days after the last snow.

ZIP 82414 is 5 miles from Buffalo Bill Dam, WY, which stands at 5,160 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 82414 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.