Last spring frost
Apr 22
Frost Dates for Hooper, UT
First fall frost
Oct 22
Growing season
180 days
Hardiness zone
7a
In an average year around Hooper, UT, the last spring frost (32°F) is about Apr 22 and the first fall frost is about Oct 22, giving roughly a 180-day growing season. To be safe most years, wait until Apr 4 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%) |
|---|---|---|---|
| Light (36°F) | May 31 | May 8 | Apr 22 |
| Freeze (32°F) | May 10 | Apr 22 | Apr 4 |
| Hard (28°F) | Apr 21 | Apr 3 | Mar 13 |
| Severe (24°F) | Apr 3 | Mar 12 | Feb 25 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 31 | May 23 | May 16 | May 12 | May 8 | May 4 | May 1 | Apr 28 | Apr 22 |
| 32°F | May 10 | May 3 | Apr 29 | Apr 26 | Apr 22 | Apr 19 | Apr 15 | Apr 11 | Apr 4 |
| 28°F | Apr 21 | Apr 16 | Apr 11 | Apr 7 | Apr 3 | Mar 31 | Mar 27 | Mar 20 | Mar 13 |
| 24°F | Apr 3 | Mar 29 | Mar 22 | Mar 16 | Mar 12 | Mar 8 | Mar 5 | Mar 2 | Feb 25 |
| 20°F | Mar 14 | Mar 9 | Mar 5 | Mar 2 | Feb 27 | Feb 24 | Feb 20 | Feb 16 | Feb 11 |
| 16°F | Mar 3 | Feb 27 | Feb 23 | Feb 19 | Feb 16 | Feb 12 | Feb 9 | Feb 4 | Jan 28 |
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%) |
|---|---|---|---|
| Light (36°F) | Sep 28 | Oct 11 | Oct 25 |
| Freeze (32°F) | Oct 7 | Oct 22 | Nov 6 |
| Hard (28°F) | Oct 18 | Nov 2 | Nov 17 |
| Severe (24°F) | Oct 25 | Nov 12 | Nov 27 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 28 | Oct 2 | Oct 5 | Oct 7 | Oct 11 | Oct 14 | Oct 16 | Oct 21 | Oct 25 |
| 32°F | Oct 7 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 1 | Nov 6 |
| 28°F | Oct 18 | Oct 23 | Oct 27 | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 17 |
| 24°F | Oct 25 | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 27 |
| 20°F | Nov 5 | Nov 10 | Nov 14 | Nov 18 | Nov 22 | Nov 25 | Nov 28 | Dec 2 | Dec 8 |
| 16°F | Nov 12 | Nov 19 | Nov 24 | Nov 28 | Dec 1 | Dec 5 | Dec 10 | Dec 15 | Dec 22 |
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: Ogden Hinkley Ap, Ut, about 6.9 miles away@if(!empty($station['elevation_ft'])), at 4,470 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 Hooper, UT?
On average, the last spring frost (32°F) around Hooper, UT is about Apr 22. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 4.
When is the first frost in the fall?
The first fall frost around Hooper, UT typically arrives about Oct 22. 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 22 on average, or Apr 4 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 180 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 84315 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026