Frost dates for Flaming Gorge, UT
At Flaming Gorge, the median last spring frost (32°F) is May 26 and the median first fall frost is Sep 23, for a typical growing season of 120 days. For a 90% chance that the last frost has passed, wait until Jun 10. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- May 26Last spring frost (median)50% chance of 32°F after this date
- Jun 10Safer planting date10% chance of 32°F after this date
- Sep 23First fall frost (median)50% chance of 32°F by this date
- 120 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 | May 26 | Jun 9 | Jun 25 |
| 32°F | May 9 | May 26 | Jun 10 |
| 28°F | Apr 26 | May 10 | May 29 |
| 24°F | Apr 11 | Apr 28 | May 14 |
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 | Sep 1 | Sep 14 | Sep 26 |
| 32°F | Sep 9 | Sep 23 | Oct 4 |
| 28°F | Sep 19 | Oct 3 | Oct 18 |
| 24°F | Sep 29 | Oct 14 | Oct 28 |
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 | 75 days | 95 days | 114 days |
| 32°F | 98 days | 120 days | 139 days |
| 28°F | 122 days | 144 days | 165 days |
| 24°F | 147 days | 170 days | 190 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 84023 | 5b | -15 to -10°F | 17 km |
| 84046 | 5b | -15 to -10°F | 32 km |
| 82938 | 5b | -15 to -10°F | 45 km |
| 84078 | 5b | -15 to -10°F | 53 km |
| 84085 | 6a | -10 to -5°F | 58 km |
| 84035 | 5b | -15 to -10°F | 59 km |
| 82901 | 5b | -15 to -10°F | 62 km |
| 84039 | 5b | -15 to -10°F | 64 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 USC00422864, at 40.9317, -109.4117, elevation 1903 m (6,244 ft).
- Data quality: Standard (24+ years of data), 26 years of freeze data.
- Average days per year at or below 32°F: 195.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Jarvie Rch (20 km)
- Manila (27 km)
- Maeser 9nw (46 km)
- Vernal Municipal Airport (55 km)
- Dinosaur Nm-Quarry Area (56 km)
- Vernal (56 km)
- Jensen (64 km)
- Neola (79 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.