Frost dates for Maeser 9nw, UT
At Maeser 9nw, the median last spring frost (32°F) is May 15 and the median first fall frost is Oct 5, for a typical growing season of 143 days. For a 90% chance that the last frost has passed, wait until Jun 7. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- May 15Last spring frost (median)50% chance of 32°F after this date
- Jun 7Safer planting date10% chance of 32°F after this date
- Oct 5First fall frost (median)50% chance of 32°F by this date
- 143 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 12 | May 29 | Jun 14 |
| 32°F | Apr 29 | May 15 | Jun 7 |
| 28°F | Apr 16 | May 2 | May 29 |
| 24°F | Mar 31 | Apr 17 | May 5 |
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 11 | Sep 26 | Oct 10 |
| 32°F | Sep 21 | Oct 5 | Oct 20 |
| 28°F | Oct 1 | Oct 17 | Oct 30 |
| 24°F | Oct 13 | Oct 27 | Nov 9 |
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 | 97 days | 119 days | 143 days |
| 32°F | 116 days | 143 days | 165 days |
| 28°F | 137 days | 166 days | 187 days |
| 24°F | 168 days | 190 days | 214 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 |
|---|---|---|---|
| 84078 | 5b | -15 to -10°F | 17 km |
| 84039 | 5b | -15 to -10°F | 18 km |
| 84076 | 5b | -15 to -10°F | 19 km |
| 84085 | 6a | -10 to -5°F | 22 km |
| 84053 | 6a | -10 to -5°F | 31 km |
| 84026 | 5b | -15 to -10°F | 33 km |
| 84035 | 5b | -15 to -10°F | 36 km |
| 84063 | 5b | -15 to -10°F | 39 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 USC00425268, at 40.5603, -109.6642, elevation 1965 m (6,448 ft).
- Data quality: Representative (10+ years), 16 years of freeze data.
- Average days per year at or below 32°F: 180.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Vernal (17 km)
- Vernal Municipal Airport (18 km)
- Dinosaur Nm-Quarry Area (33 km)
- Jensen (35 km)
- Fort Duchesne (35 km)
- Neola (36 km)
- Roosevelt Radio (39 km)
- Flaming Gorge (46 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.