Frost Dates for 87020 — Grants, New Mexico

Half of springs at Grants Airport, NM see their last 32°F night by May 17; only one in ten is past it by April 30, and one in ten still has one after June 1. Planting tender crops after May 24 leaves a 30% risk of a frost on them, after May 29 20%, and after June 1 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 46% of the 70 New Mexico 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 21 one year in ten, and holds off past October 14 one year in ten. A hard freeze of 28°F follows 8 days later, around October 11; in spring the one-in-ten date for 28°F is May 21, 11 days before the 32°F one. The freeze-free season lasts 137 days in a typical year, shorter than at 81% of the 70 New Mexico stations; it reaches 156 days one year in ten and falls short of 118 one year in ten. On average 182 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 14 days longer, to about May 31, and return around September 25. Severe cold of 16°F or below comes every winter, usually between November 8 and March 23.

July is the warmest month at Grants Airport, NM, averaging 92°F by day and 55°F at night; December is the coldest at 50°F and 14°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 87% of years and June still brings one in 13% of years.

Warmth for growing adds up to 2,929 growing degree days a year (base 50°F), fewer than at 63% of the 70 New Mexico stations. 33% of them (978) have built up by the end of June, and July adds the most, 733. Precipitation totals 9.7 inches a year, most in August (1.8") and least in February (0.4"); May to September bring 59% of it.

The nearest other station, Thoreau 12 SE, NM, 18 miles northwest of Grants and 905 feet higher, has a last frost 12 days later (May 29), a first frost 7 days earlier (September 26), a season 19 days shorter.

The first measurable snow (0.1 inch or more) in Grants usually arrives around December 8, and the last of the season around February 19. Those are the middle dates across the winters of 1991–2020 at Grants Airport, NM, 3.1 miles away: half of years saw snow earlier, half later. Snow fell in 87% of those winters. The last 32°F night of spring typically comes 87 days after the last snow.

ZIP 87020 is 3 miles from Grants Airport, NM, which stands at 6,520 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 87020 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.