Frost Dates for 84315 — Hooper, Utah

Half of springs at Ogden Hinkley Airport, UT see their last 32°F night by April 22; only one in ten is past it by April 4, and one in ten still has one after May 10. Planting tender crops after April 29 leaves a 30% risk of a frost on them, after May 3 20%, and after May 10 10%. The 18 days between the even-odds date and the one-in-ten date is narrower than at 47% of the 66 Utah stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 22 in half of years, as early as October 7 one year in ten, and holds off past November 6 one year in ten. A hard freeze of 28°F follows 11 days later, around November 2; in spring the one-in-ten date for 28°F is April 21, 19 days before the 32°F one. The freeze-free season lasts 180 days in a typical year, longer than at 77% of the 66 Utah stations; it reaches 204 days one year in ten and falls short of 158 one year in ten. On average 121 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 16 days longer, to about May 8, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 1 and February 16.

July is the warmest month at Ogden Hinkley Airport, UT, averaging 91°F by day and 65°F at night; January is the coldest at 36°F and 21°F. A freezing night is all but certain in every month from November 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 26% of years.

Warmth for growing adds up to 3,226 growing degree days a year (base 50°F), more than at 73% of the 66 Utah stations. 29% of them (943) have built up by the end of June, and July adds the most, 869. Precipitation totals 16.5 inches a year, most in May (2.2") and least in July (0.4"); May to September bring 33% of it.

The nearest other station, Ogden Sugar Factory, UT, 6 miles northeast of Hooper and 190 feet lower, has the same 50% last-frost date, a first frost 4 days earlier (October 18), a season 3 days shorter.

The first measurable snow (0.1 inch or more) in Hooper usually arrives around November 29, and the last of the season around March 3. Those are the middle dates across the winters of 1991–2020 at Ogden Pioneer Ph, UT, 9.7 miles away: half of years saw snow earlier, half later. Snow fell in 89% of those winters. The last 32°F night of spring typically comes 50 days after the last snow.

ZIP 84315 is 5 miles from Ogden Hinkley Airport, UT, which stands at 4,470 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 84015 (Clearfield). The 2023 USDA Plant Hardiness Zone Map lists ZIP 84315 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.