Frost Dates for 84651 — Payson, Utah

Half of springs at Santaquin Chlorinator, UT see their last 32°F night by May 4; only one in ten is past it by April 18, and one in ten still has one after May 28. Planting tender crops after May 14 leaves a 30% risk of a frost on them, after May 19 20%, and after May 28 10%. The 24 days between the even-odds date and the one-in-ten date is wider than at 92% of the 66 Utah stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by October 11 in half of years, as early as September 27 one year in ten, and holds off past October 26 one year in ten. A hard freeze of 28°F follows 12 days later, around October 23; in spring the one-in-ten date for 28°F is May 10, 18 days before the 32°F one. The freeze-free season lasts 157 days in a typical year, longer than at 52% of the 66 Utah stations; it reaches 179 days one year in ten and falls short of 132 one year in ten. On average 144 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 19 days longer, to about May 23, and return around October 1. Severe cold of 16°F or below comes every winter, usually between November 22 and February 26.

July is the warmest month at Santaquin Chlorinator, UT, averaging 90°F by day and 63°F at night; January is the coldest at 37°F and 20°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 60% of years.

Warmth for growing adds up to 3,017 growing degree days a year (base 50°F), more than at 59% of the 66 Utah stations. 28% of them (859) have built up by the end of June, and July adds the most, 814. Precipitation totals 18.2 inches a year, most in April (2.2") and least in July (0.7"); May to September bring 30% of it.

The nearest other station, Spanish Fk Pwr House, UT, 7 miles northeast of Payson and 440 feet lower, has a last frost 9 days earlier (April 25), a first frost 7 days later (October 18), a season 17 days longer.

The first measurable snow (0.1 inch or more) in Payson usually arrives around November 8, and the last of the season around April 8. Those are the middle dates across the winters of 1991–2020 at Santaquin Chlorinator, UT, 5.6 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 26 days after the last snow.

ZIP 84651 is 6 miles from Santaquin Chlorinator, UT, which stands at 5,160 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 84651 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.