Frost dates for Johnson Pass, UT
At Johnson Pass, 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 142 days. For a 90% chance that the last frost has passed, wait until Jun 4. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- May 15Last spring frost (median)50% chance of 32°F after this date
- Jun 4Safer planting date10% chance of 32°F after this date
- Oct 5First fall frost (median)50% chance of 32°F by this date
- 142 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 30 | Jun 15 |
| 32°F | Apr 27 | May 15 | Jun 4 |
| 28°F | Apr 12 | Apr 30 | May 20 |
| 24°F | Mar 28 | Apr 16 | May 7 |
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 25 | Oct 8 |
| 32°F | Sep 22 | Oct 5 | Oct 22 |
| 28°F | Oct 1 | Oct 16 | Nov 1 |
| 24°F | Oct 12 | Oct 29 | Nov 14 |
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 | 95 days | 117 days | 140 days |
| 32°F | 118 days | 142 days | 166 days |
| 28°F | 146 days | 169 days | 191 days |
| 24°F | 170 days | 195 days | 219 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 |
|---|---|---|---|
| 84022 | 6b | -5 to 0°F | 3 km |
| 84069 | 6a | -10 to -5°F | 11 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 USC00424362, at 40.3375, -112.6114, elevation 1701 m (5,580 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 154.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Grantsville 2w (31 km)
- Vernon (31 km)
- Dugway (31 km)
- Tooele (33 km)
- Fairfield (45 km)
- Garfield (55 km)
- Utah Lake Lehi (61 km)
- Draper-Point Of Mountain (63 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.