Frost Dates for 84720 — Cedar City, Utah

Half of springs at Cedar City Municipal Airport, UT see their last 32°F night by May 21; only one in ten is past it by May 4, and one in ten still has one after June 8. Planting tender crops after May 30 leaves a 30% risk of a frost on them, after June 2 20%, and after June 8 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 September 29 in half of years, as early as September 17 one year in ten, and holds off past October 14 one year in ten. A hard freeze of 28°F follows 10 days later, around October 9; in spring the one-in-ten date for 28°F is May 25, 14 days before the 32°F one. The freeze-free season lasts 130 days in a typical year, shorter than at 67% of the 66 Utah stations; it reaches 151 days one year in ten and falls short of 108 one year in ten. On average 169 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 13 days longer, to about June 3, and return around September 21. Severe cold of 16°F or below comes every winter, usually between November 10 and March 13.

July is the warmest month at Cedar City Municipal Airport, UT, averaging 91°F by day and 57°F at night; December is the coldest at 42°F and 16°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 24% of years.

Warmth for growing adds up to 2,730 growing degree days a year (base 50°F), fewer than at 55% of the 66 Utah stations. 29% of them (792) have built up by the end of June, and July adds the most, 746. Precipitation totals 11.0 inches a year, most in March (1.2") and least in June (0.5"); May to September bring 37% of it.

The nearest other station, Brian Head, UT, 18 miles east of Cedar City and 4,184 feet higher, has a last frost 31 days later (June 21), a first frost 17 days earlier (September 12), a season 48 days shorter.

The first measurable snow (0.1 inch or more) in Cedar City usually arrives around November 6, and the last of the season around April 30. Those are the middle dates across the winters of 1991–2020 at Cedar City, UT, 7.4 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 21 days after the last snow.

ZIP 84720 is 5 miles from Cedar City Municipal Airport, UT, which stands at 5,586 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 84720 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.