Frost Dates for 85941 — Whiteriver, Arizona

Half of springs at Pinetop 2E, AZ see their last 32°F night by May 22; only one in ten is past it by May 6, and one in ten still has one after June 4. Planting tender crops after May 28 leaves a 30% risk of a frost on them, after June 1 20%, and after June 4 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 99% of the 98 Arizona stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 6 in half of years, as early as September 24 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 11 days later, around October 17; in spring the one-in-ten date for 28°F is May 23, 12 days before the 32°F one. The freeze-free season lasts 138 days in a typical year, shorter than at 93% of the 98 Arizona stations; it reaches 158 days one year in ten and falls short of 120 one year in ten. On average 163 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 3, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 24 and March 12.

July is the warmest month at Pinetop 2E, AZ, averaging 82°F by day and 52°F at night; December is the coldest at 45°F and 19°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 20% of years.

Warmth for growing adds up to 2,095 growing degree days a year (base 50°F), fewer than at 98% of the 102 Arizona stations. 31% of them (655) have built up by the end of June, and July adds the most, 535. Precipitation totals 24.1 inches a year, most in August (4.0") and least in June (0.6"); May to September bring 45% of it.

The nearest other station, Show Low Airport, AZ, 29 miles north of Whiteriver and 789 feet lower, has a last frost 17 days earlier (May 5), a first frost 9 days later (October 15), a season 24 days longer.

The first measurable snow (0.1 inch or more) in Whiteriver usually arrives around November 17, and the last of the season around April 18. Those are the middle dates across the winters of 1991–2020 at Pinetop 2E, AZ, 20 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 34 days after the last snow.

ZIP 85941 is 20 miles from Pinetop 2E, AZ, which stands at 7,200 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 85941 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.