Growing season
80 days
Frost Dates for Tropic, UT
Hardiness zone
6a
Frost normals for this location are limited (the nearest long-term weather station may not report all thresholds). The available data is shown below.
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%) |
|---|---|---|---|
| Hard (28°F) | Jun 24 | Jun 9 | May 25 |
| Severe (24°F) | Jun 8 | May 23 | May 4 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 28°F | Jun 24 | Jun 20 | Jun 15 | Jun 12 | Jun 9 | Jun 6 | Jun 4 | Jun 1 | May 25 |
| 24°F | Jun 8 | Jun 3 | May 31 | May 27 | May 23 | May 18 | May 14 | May 10 | May 4 |
| 20°F | May 23 | May 15 | May 11 | May 6 | May 3 | Apr 30 | Apr 26 | Apr 22 | Apr 16 |
| 16°F | May 5 | Apr 30 | Apr 25 | Apr 21 | Apr 17 | Apr 12 | Apr 9 | Apr 4 | Mar 29 |
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%) |
|---|---|---|---|
| Hard (28°F) | Sep 11 | Sep 24 | Oct 7 |
| Severe (24°F) | Sep 22 | Oct 4 | Oct 19 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 28°F | Sep 11 | Sep 16 | Sep 20 | Sep 22 | Sep 24 | Sep 27 | Sep 29 | Oct 2 | Oct 7 |
| 24°F | Sep 22 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 14 | Oct 19 |
| 20°F | Oct 1 | Oct 4 | Oct 8 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 25 | Oct 30 |
| 16°F | Oct 9 | Oct 15 | Oct 19 | Oct 23 | Oct 25 | Oct 28 | Nov 1 | Nov 5 | Nov 10 |
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: Bryce Canyon Ap, Ut, about 12.9 miles away@if(!empty($station['elevation_ft'])), at 7,586 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
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 80 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 84764 Planting calendar → Utah frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026