Frost Dates for 84043 — Lehi, Utah

Half of springs at Utah Lake Lehi, UT see their last 32°F night by April 30; only one in ten is past it by April 14, and one in ten still has one after May 27. Planting tender crops after May 8 leaves a 30% risk of a frost on them, after May 16 20%, and after May 27 10%. The 27 days between the even-odds date and the one-in-ten date is wider than at 98% 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 9 in half of years, as early as September 26 one year in ten, and holds off past October 25 one year in ten. A hard freeze of 28°F follows 13 days later, around October 22; in spring the one-in-ten date for 28°F is May 2, 25 days before the 32°F one. The freeze-free season lasts 159 days in a typical year, longer than at 53% of the 66 Utah stations; it reaches 182 days one year in ten and falls short of 131 one year in ten. On average 149 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 20 days longer, to about May 20, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 24 and February 17.

July is the warmest month at Utah Lake Lehi, UT, averaging 92°F by day and 59°F at night; January is the coldest at 38°F and 19°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 45% of years.

Warmth for growing adds up to 2,887 growing degree days a year (base 50°F), more than at 53% of the 66 Utah stations. 29% of them (847) have built up by the end of June, and July adds the most, 793. Precipitation totals 13.2 inches a year, most in April (1.6") and least in June (0.6"); May to September bring 38% of it.

The nearest other station, Pleasant Grove, UT, 8 miles east of Lehi and 187 feet higher, has a last frost 13 days earlier (April 17), a first frost 16 days later (October 25), a season 29 days longer.

The first measurable snow (0.1 inch or more) in Lehi usually arrives around November 23, and the last of the season around March 21. Those are the middle dates across the winters of 1991–2020 at Utah Lake Lehi, UT, 0.6 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 40 days after the last snow.

ZIP 84043 is under a mile from Utah Lake Lehi, UT, which stands at 4,505 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 84043 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.