Frost dates for Fairfield, UT
At Fairfield, the median last spring frost (32°F) is Jun 2 and the median first fall frost is Sep 16, for a typical growing season of 103 days. For a 90% chance that the last frost has passed, wait until Jun 24. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- Jun 2Last spring frost (median)50% chance of 32°F after this date
- Jun 24Safer planting date10% chance of 32°F after this date
- Sep 16First fall frost (median)50% chance of 32°F by this date
- 103 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 |
|---|---|---|---|
| 32°F | May 18 | Jun 2 | Jun 24 |
| 28°F | May 2 | May 19 | Jun 10 |
| 24°F | Apr 17 | May 4 | May 26 |
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 |
|---|---|---|---|
| 32°F | Sep 1 | Sep 16 | Sep 29 |
| 28°F | Sep 10 | Sep 26 | Oct 7 |
| 24°F | Sep 23 | Oct 5 | Oct 19 |
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 | 51 days | 76 days | 99 days |
| 32°F | 76 days | 103 days | 125 days |
| 28°F | 101 days | 127 days | 150 days |
| 24°F | 127 days | 152 days | 174 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 |
|---|---|---|---|
| 84013 | 6a | -10 to -5°F | 4 km |
| 84071 | 6b | -5 to 0°F | 18 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 USC00422696, at 40.2622, -112.0897, elevation 1487 m (4,880 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 197.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Utah Lake Lehi (20 km)
- Draper-Point Of Mountain (30 km)
- Orem Trtmt Plant (30 km)
- Pleasant Grove (32 km)
- Vernon (35 km)
- Alpine (35 km)
- Tooele (36 km)
- Provo Byu (37 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.