Last spring frost
Jun 21
Frost Dates for Brian Head, UT
First fall frost
Sep 12
Growing season
82 days
Hardiness zone
6a
In an average year around Brian Head, UT, the last spring frost (32°F) is about Jun 21 and the first fall frost is about Sep 12, giving roughly a 82-day growing season. To be safe most years, wait until Jun 6 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Freeze (32°F) | Jul 6 | Jun 21 | Jun 6 |
| Hard (28°F) | Jun 24 | Jun 7 | May 25 |
| Severe (24°F) | Jun 13 | May 28 | May 11 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 32°F | Jul 6 | Jun 30 | Jun 27 | Jun 24 | Jun 21 | Jun 18 | Jun 14 | Jun 11 | Jun 6 |
| 28°F | Jun 24 | Jun 19 | Jun 14 | Jun 11 | Jun 7 | Jun 5 | Jun 2 | May 31 | May 25 |
| 24°F | Jun 13 | Jun 6 | Jun 3 | May 31 | May 28 | May 23 | May 20 | May 16 | May 11 |
| 20°F | May 31 | May 22 | May 18 | May 15 | May 12 | May 9 | May 6 | May 3 | Apr 30 |
| 16°F | May 16 | May 10 | May 6 | May 4 | May 2 | Apr 30 | Apr 27 | Apr 24 | Apr 18 |
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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Freeze (32°F) | Sep 1 | Sep 12 | Sep 23 |
| Hard (28°F) | Sep 10 | Sep 22 | Oct 1 |
| Severe (24°F) | Sep 18 | Oct 1 | Oct 12 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 32°F | Sep 1 | Sep 4 | Sep 8 | Sep 10 | Sep 12 | Sep 14 | Sep 17 | Sep 19 | Sep 23 |
| 28°F | Sep 10 | Sep 14 | Sep 17 | Sep 20 | Sep 22 | Sep 24 | Sep 26 | Sep 28 | Oct 1 |
| 24°F | Sep 18 | Sep 23 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 12 |
| 20°F | Sep 27 | Oct 1 | Oct 3 | Oct 6 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 22 |
| 16°F | Oct 4 | Oct 8 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 29 | Nov 4 |
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
@endif These dates are computed from the nearest official weather station with long-term records: Brian Head, Ut, about 4.2 miles away@if(!empty($station['elevation_ft'])), at 9,770 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
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 Brian Head, UT?
On average, the last spring frost (32°F) around Brian Head, UT is about Jun 21. In cooler years it can run later, so for a safer bet many gardeners wait until Jun 6.
When is the first frost in the fall?
The first fall frost around Brian Head, UT typically arrives about Sep 12. 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 Jun 21 on average, or Jun 6 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 82 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 84719 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026