Frost dates for Carefree, AZ
At Carefree, the median last spring frost (32°F) is Feb 4 and the median first fall frost is Dec 16, for a typical growing season of 313 days. For a 90% chance that the last frost has passed, wait until Mar 9. Nearby ZIP codes are in USDA hardiness zones 9b to 10a.
- Feb 4Last spring frost (median)50% chance of 32°F after this date
- Mar 9Safer planting date10% chance of 32°F after this date
- Dec 16First fall frost (median)50% chance of 32°F by this date
- 313 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 | Jan 31 | Mar 5 | Apr 2 |
| 32°F | Jan 3 | Feb 4 | Mar 9 |
| 28°F | Dec 19 | Jan 14 | Feb 22 |
| 24°F | Dec 19 | Jan 7 | Feb 14 |
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 | Nov 13 | Dec 1 | Dec 18 |
| 32°F | Nov 24 | Dec 16 | Jan 15 |
| 28°F | Dec 5 | Jan 1 | Feb 9 |
| 24°F | Dec 15 | Jan 6 | Feb 11 |
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 | 236 days | 269 days | 307 days |
| 32°F | 273 days | 313 days | 351 days |
| 28°F | 316 days | 357 days | 365 days |
| 24°F | 350 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 98% |
| 28°F | 60% |
| 24°F | 15% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 85377 | 9b | 25 to 30°F | 1 km |
| 85266 | 10a | 30 to 35°F | 6 km |
| 85331 | 9b | 25 to 30°F | 8 km |
| 85262 | 9b | 25 to 30°F | 10 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 USC00021282, at 33.8161, -111.9019, elevation 771 m (2,530 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 6.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Pinnacle Peak (11 km)
- Scottsdale Muni Airport (22 km)
- Phoenix Deer Valley Muni Airport (22 km)
- Fountain Hills (29 km)
- Tempe Asu (43 km)
- Phoenix Sky Harbor Intl Airport (44 km)
- Youngtown (44 km)
- Stewart Mountain Dam (44 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.