Frost Dates for 81082 — Trinidad, Colorado

Half of springs at Trinidad, CO see their last 32°F night by April 30; only one in ten is past it by April 16, and one in ten still has one after May 11. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 7 20%, and after May 11 10%. The 11 days between the even-odds date and the one-in-ten date is narrower than at 97% of the 110 Colorado stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 15 in half of years, as early as October 1 one year in ten, and holds off past October 29 one year in ten. A hard freeze of 28°F follows 9 days later, around October 24; in spring the one-in-ten date for 28°F is May 3, 8 days before the 32°F one. The freeze-free season lasts 167 days in a typical year, longer than at 94% of the 110 Colorado stations; it reaches 186 days one year in ten and falls short of 148 one year in ten. On average 146 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 8 days longer, to about May 8, and return around October 6. Severe cold of 16°F or below comes every winter, usually between November 20 and March 13.

July is the warmest month at Trinidad, CO, averaging 88°F by day and 61°F at night; December is the coldest at 49°F and 22°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 46% of years.

Warmth for growing adds up to 3,322 growing degree days a year (base 50°F), more than at 86% of the 110 Colorado stations. 35% of them (1,161) have built up by the end of June, and July adds the most, 751. Precipitation totals 14.8 inches a year, most in July (2.6") and least in January (0.5"); May to September bring 61% of it.

The nearest other station, Raton Municipal Crews Airport, NM, 31 miles south of Trinidad and 319 feet higher, has a last frost 11 days later (May 11), a first frost 11 days earlier (October 4), a season 22 days shorter.

The first measurable snow (0.1 inch or more) in Trinidad usually arrives around November 3, and the last of the season around April 13. Those are the middle dates across the winters of 1991–2020 at Trinidad, CO, 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 17 days after the last snow.

ZIP 81082 is 1 mile from Trinidad, CO, which stands at 6,030 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 81082 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.