Frost dates for Bellemont WFO, AZ
At Bellemont WFO, the median last spring frost (32°F) is Jun 21 and the median first fall frost is Sep 17, for a typical growing season of 85 days. For a 90% chance that the last frost has passed, wait until Jul 4. Nearby ZIP codes are in USDA hardiness zones 5b to 6b.
- Jun 21Last spring frost (median)50% chance of 32°F after this date
- Jul 4Safer planting date10% chance of 32°F after this date
- Sep 17First fall frost (median)50% chance of 32°F by this date
- 85 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 | Jun 9 | Jun 21 | Jul 4 |
| 28°F | May 28 | Jun 9 | Jun 22 |
| 24°F | May 7 | May 28 | Jun 11 |
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 3 | Sep 17 | Sep 29 |
| 28°F | Sep 15 | Sep 27 | Oct 9 |
| 24°F | Sep 25 | Oct 5 | Oct 20 |
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 | 41 days | 64 days | 81 days |
| 32°F | 65 days | 85 days | 103 days |
| 28°F | 91 days | 107 days | 126 days |
| 24°F | 112 days | 132 days | 157 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 |
|---|---|---|---|
| 86015 | 5b | -15 to -10°F | 1 km |
| 86018 | 6b | -5 to 0°F | 13 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 USC00020678, at 35.2303, -111.8222, elevation 2180 m (7,152 ft).
- Data quality: Representative (10+ years), 18 years of freeze data.
- Average days per year at or below 32°F: 239.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Fort Valley (8 km)
- Flagstaff 4 SW (11 km)
- Flagstaff Pulliam Airport (17 km)
- Walnut Canyon National Monument (29 km)
- Sunset Crater National Monument (30 km)
- Oak Creek Canyon (31 km)
- Williams (34 km)
- Mund's Park (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.