ZIP 84790 Zone 8b

Utah · USDA zone 8b, average annual extreme minimum 15°F to 20°F.

Nearest qualified station: ST GEORGE, UT US (USC00427516), 5.7 miles from the Census ZCTA internal point for this ZIP.

Median last 32°F is March 14. Median first 32°F is November 10. The 50% growing-season length is 239 days. The green band runs from the median last frost to the median first frost. Thin ticks mark the 10%, 50%, and 90% dates.

Outside the median season Growing seasonTicks: 10%, 50%, and 90%

Last 32°F in spring

NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.

ProbabilityDateHow to read it
90%February 27Earlier date. A last 32°F on or after this day is common.
50%March 14Median.
10%April 6Later date. A last 32°F on or after this day is uncommon.

First 32°F in fall

NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.

ProbabilityDateHow to read it
10%October 27Earlier date. A first 32°F on or before this day is uncommon.
50%November 10Median.
90%November 22Later date. A first 32°F on or before this day is common.

32°F growing-season length

Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.

Probability the season is at least this longDays
10%260
50%239
90%212

28°F threshold

10%50%90%
Last, on or afterMarch 17February 27February 7
First, on or beforeNovember 7November 20December 3
Season at least290 days266 days243 days

36°F threshold

10%50%90%
Last, on or afterApril 21April 3March 17
First, on or beforeOctober 19November 1November 12
Season at least229 days208 days186 days

Station ST GEORGE, UT US (USC00427516). Completeness flag R, 23 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 870.8 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Methodology · Utah cities