Frost Dates for 86023 — Grand Canyon, Arizona

Half of springs at Grand Canyon Np Airport, AZ see their last 32°F night by June 17; only one in ten is past it by June 3, and one in ten still has one after July 1. Planting tender crops after June 23 leaves a 30% risk of a frost on them, after June 26 20%, and after July 1 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 95% of the 98 Arizona stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 24 in half of years, as early as September 12 one year in ten, and holds off past October 6 one year in ten. A hard freeze of 28°F follows 9 days later, around October 3; in spring the one-in-ten date for 28°F is June 21, 10 days before the 32°F one. The freeze-free season lasts 97 days in a typical year, the shortest of the 98 Arizona stations; it reaches 116 days one year in ten and falls short of 80 one year in ten. On average 226 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 11 days longer, to about June 28, and return around September 15. Severe cold of 16°F or below comes every winter, usually between November 5 and April 12.

July is the warmest month at Grand Canyon Np Airport, AZ, averaging 85°F by day and 49°F at night; December is the coldest at 44°F and 14°F. A freezing night is all but certain in every month from October to June (a 90% chance or more). August is the only month with under a 10% chance of a 32°F night. In spring, July still brings one in 10% of years.

Warmth for growing adds up to 1,763 growing degree days a year (base 50°F), fewer than at 99% of the 102 Arizona stations. 24% of them (422) have built up by the end of June, and July adds the most, 525. Precipitation totals 13.4 inches a year, most in August (2.1") and least in June (0.4"); May to September bring 46% of it.

The nearest other station, Williams 35 NNW, AZ, 17 miles southwest of Grand Canyon and 616 feet lower, has a last frost 39 days earlier (May 9), a first frost 25 days later (October 19), a season 64 days longer.

The first measurable snow (0.1 inch or more) in Grand Canyon usually arrives around November 28, and the last of the season around April 2. Those are the middle dates across the winters of 1991–2020 at Grand Canyon Np 2, AZ, 14 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 76 days after the last snow.

ZIP 86023 is 8 miles from Grand Canyon Np Airport, AZ, which stands at 6,606 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 86023 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.