Frost dates for Sierra Vista, AZ
At Sierra Vista, the median last spring frost (32°F) is Apr 5 and the median first fall frost is Nov 9, for a typical growing season of 216 days. For a 90% chance that the last frost has passed, wait until Apr 21. Nearby ZIP codes are in USDA hardiness zone 8b.
- Apr 5Last spring frost (median)50% chance of 32°F after this date
- Apr 21Safer planting date10% chance of 32°F after this date
- Nov 9First fall frost (median)50% chance of 32°F by this date
- 216 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 | Apr 5 | Apr 20 | May 4 |
| 32°F | Mar 15 | Apr 5 | Apr 21 |
| 28°F | Feb 21 | Mar 15 | Apr 5 |
| 24°F | Jan 20 | Feb 19 | Mar 15 |
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 | Oct 15 | Oct 30 | Nov 12 |
| 32°F | Oct 23 | Nov 9 | Nov 23 |
| 28°F | Nov 4 | Nov 21 | Dec 5 |
| 24°F | Nov 16 | Dec 3 | Dec 21 |
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 | 171 days | 191 days | 211 days |
| 32°F | 194 days | 216 days | 239 days |
| 28°F | 220 days | 248 days | 276 days |
| 24°F | 256 days | 287 days | 323 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 |
|---|---|---|---|
| 85650 | 8b | 15 to 20°F | 9 km |
| 85635 | 8b | 15 to 20°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 USC00027880, at 31.5369, -110.2808, elevation 1404 m (4,606 ft).
- Data quality: Representative (10+ years), 19 years of freeze data.
- Average days per year at or below 32°F: 45.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Fort Huachuca Pioneer Airfield (16 km)
- Coronado Nmem (21 km)
- Elgin 5 S (22 km)
- Canelo 1 NW (24 km)
- Tombstone (28 km)
- Kartchner Caverns (34 km)
- Bisbee 1wnw (35 km)
- Benson 6se (38 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.