Frost Dates for 81211 — Buena Vista, Colorado

Half of springs at Buena Vista 2S, CO see their last 32°F night by May 27; only one in ten is past it by May 13, and one in ten still has one after June 11. Planting tender crops after June 2 leaves a 30% risk of a frost on them, after June 6 20%, and after June 11 10%. The 15 days between the even-odds date and the one-in-ten date is wider than at 56% of the 110 Colorado stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 23 in half of years, as early as September 10 one year in ten, and holds off past October 4 one year in ten. A hard freeze of 28°F follows 9 days later, around October 2; in spring the one-in-ten date for 28°F is June 1, 10 days before the 32°F one. The freeze-free season lasts 116 days in a typical year, shorter than at 69% of the 110 Colorado stations; it reaches 135 days one year in ten and falls short of 97 one year in ten. On average 208 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 12 days longer, to about June 8, and return around September 13. Severe cold of 16°F or below comes every winter, usually between October 31 and April 10.

July is the warmest month at Buena Vista 2S, CO, averaging 83°F by day and 49°F at night; December is the coldest at 40°F and 11°F. A freezing night is all but certain in every month from October to May (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, June still brings one in 37% of years.

Warmth for growing adds up to 1,641 growing degree days a year (base 50°F), fewer than at 72% of the 110 Colorado stations. 28% of them (455) have built up by the end of June, and July adds the most, 502. Precipitation totals 9.8 inches a year, most in August (1.6") and least in January (0.3"); May to September bring 60% of it.

The nearest other station, Twin Lakes Rsvr, CO, 19 miles northwest of Buena Vista and 1,282 feet higher, has a last frost 20 days later (June 16), a first frost 13 days earlier (September 10), a season 31 days shorter.

The first measurable snow (0.1 inch or more) in Buena Vista usually arrives around October 22, and the last of the season around May 4. Those are the middle dates across the winters of 1991–2020 at Buena Vista 2S, CO, 3.1 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 23 days after the last snow.

ZIP 81211 is 3 miles from Buena Vista 2S, CO, which stands at 7,954 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 81211 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.