Frost Dates for 84737 — Hurricane, Utah

Half of springs at La Verkin, UT see their last 32°F night by April 1; only one in ten is past it by March 5, and one in ten still has one after April 24. Planting tender crops after April 10 leaves a 30% risk of a frost on them, after April 16 20%, and after April 24 10%. The 23 days between the even-odds date and the one-in-ten date is wider than at 86% 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 November 5 in half of years, as early as October 23 one year in ten, and holds off past November 17 one year in ten. A hard freeze of 28°F follows 10 days later, around November 15; in spring the one-in-ten date for 28°F is April 2, 22 days before the 32°F one. The freeze-free season lasts 217 days in a typical year, longer than at 97% of the 66 Utah stations; it reaches 245 days one year in ten and falls short of 190 one year in ten. On average 75 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 April 20, and return around October 27. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 68%.

July is the warmest month at La Verkin, UT, averaging 98°F by day and 68°F at night; December is the coldest at 51°F and 28°F. A freezing night is all but certain in every month from November to February (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, March still brings one in 87% of years and April still brings one in 48% of years.

Warmth for growing adds up to 4,952 growing degree days a year (base 50°F), more than at 98% of the 66 Utah stations. 36% of them (1,781) have built up by the end of June, and July adds the most, 1,021. Precipitation totals 11.7 inches a year, most in February (1.8") and least in June (0.2"); May to September bring 27% of it.

The nearest other station, Colorado City, AZ, 18 miles southeast of Hurricane and 1,807 feet higher, has a last frost 25 days later (April 26), a first frost 11 days earlier (October 25), a season 37 days shorter.

The first measurable snow (0.1 inch or more) in Hurricane usually arrives around January 2, and the last of the season around February 3. Those are the middle dates across the winters of 1991–2020 at La Verkin, UT, 5 miles away: half of years saw snow earlier, half later. Snow fell in 59% of those winters. The last 32°F night of spring typically comes 57 days after the last snow.

ZIP 84737 is 5 miles from La Verkin, UT, which stands at 3,194 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 84737 in zone 8b, the band where the coldest night of the year averaged 15 to 20°F (-9.4 to -6.7°C) over 1991–2020; a zone describes winter lows, not frost dates.