Frost dates for St. George, UT
At St. George, the median last spring frost (32°F) is Mar 14 and the median first fall frost is Nov 10, for a typical growing season of 239 days. For a 90% chance that the last frost has passed, wait until Apr 6. Nearby ZIP codes are in USDA hardiness zone 8b.
- Mar 14Last spring frost (median)50% chance of 32°F after this date
- Apr 6Safer planting date10% chance of 32°F after this date
- Nov 10First fall frost (median)50% chance of 32°F by this date
- 239 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Mar 17 | Apr 3 | Apr 21 |
| 32°F | Feb 27 | Mar 14 | Apr 6 |
| 28°F | Feb 7 | Feb 27 | Mar 17 |
| 24°F | Jan 18 | Feb 9 | Feb 28 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Oct 19 | Nov 1 | Nov 12 |
| 32°F | Oct 27 | Nov 10 | Nov 22 |
| 28°F | Nov 7 | Nov 20 | Dec 3 |
| 24°F | Nov 18 | Dec 1 | Dec 18 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 186 days | 208 days | 229 days |
| 32°F | 212 days | 239 days | 260 days |
| 28°F | 243 days | 266 days | 290 days |
| 24°F | 272 days | 294 days | 322 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 84770 | 8b | 15 to 20°F | 3 km |
| 84790 | 8b | 15 to 20°F | 9 km |
| 84780 | 8b | 15 to 20°F | 12 km |
| 84738 | 8b | 15 to 20°F | 14 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00427516, at 37.1189, -113.6067, elevation 871 m (2,857 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 62.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Veyo Powerhouse (26 km)
- La Verkin (31 km)
- Lytle Rch (37 km)
- New Harmony (47 km)
- Enterprise (52 km)
- Zion National Park (56 km)
- Enterprise Beryl Junction (72 km)
- Cedar City (76 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.