Harman US

Frost Dates for East Carbon, UT

Last spring frost
Apr 26
First fall frost
Oct 25
Growing season
181 days
Hardiness zone
6b

In an average year around East Carbon, UT, the last spring frost (32°F) is about Apr 26 and the first fall frost is about Oct 25, giving roughly a 181-day growing season. To be safe most years, wait until Apr 8 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - East Carbon, UT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Jun 2 May 11 Apr 25
Freeze (32°F) May 18 Apr 26 Apr 8
Hard (28°F) Apr 26 Apr 7 Mar 15
Severe (24°F) Apr 8 Mar 14 Feb 20
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Jun 2 May 24 May 20 May 16 May 11 May 6 May 2 Apr 30 Apr 25
32°F May 18 May 9 May 2 Apr 29 Apr 26 Apr 22 Apr 18 Apr 13 Apr 8
28°F Apr 26 Apr 19 Apr 15 Apr 11 Apr 7 Apr 3 Mar 31 Mar 24 Mar 15
24°F Apr 8 Mar 31 Mar 25 Mar 18 Mar 14 Mar 9 Mar 5 Mar 1 Feb 20
20°F Mar 16 Mar 9 Mar 5 Mar 1 Feb 26 Feb 21 Feb 16 Feb 10 Feb 1
16°F Mar 3 Feb 27 Feb 20 Feb 14 Feb 9 Feb 4 Jan 28 Jan 16 Dec 31

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - East Carbon, UT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 27 Oct 12 Oct 29
Freeze (32°F) Oct 7 Oct 25 Nov 11
Hard (28°F) Oct 22 Nov 7 Nov 22
Severe (24°F) Nov 1 Nov 18 Dec 4
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 27 Oct 2 Oct 5 Oct 9 Oct 12 Oct 16 Oct 19 Oct 23 Oct 29
32°F Oct 7 Oct 13 Oct 18 Oct 22 Oct 25 Oct 29 Nov 1 Nov 5 Nov 11
28°F Oct 22 Oct 28 Nov 1 Nov 4 Nov 7 Nov 11 Nov 15 Nov 18 Nov 22
24°F Nov 1 Nov 6 Nov 10 Nov 15 Nov 18 Nov 20 Nov 24 Nov 28 Dec 4
20°F Nov 9 Nov 16 Nov 21 Nov 24 Nov 28 Dec 3 Dec 7 Dec 11 Dec 18
16°F Nov 19 Nov 27 Dec 2 Dec 6 Dec 10 Dec 15 Dec 20 Dec 27 Jan 8

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Sunnyside City, Ut, about 1.8 miles away@if(!empty($station['elevation_ft'])), at 6,511 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in East Carbon, UT?

On average, the last spring frost (32°F) around East Carbon, UT is about Apr 26. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 8.

When is the first frost in the fall?

The first fall frost around East Carbon, UT typically arrives about Oct 25. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 26 on average, or Apr 8 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 181 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 84539 Planting calendar → Utah frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026