Frost dates for Tumacacori National Monument, AZ
At Tumacacori National Monument, the median last spring frost (32°F) is Apr 5 and the median first fall frost is Nov 10, for a typical growing season of 217 days. For a 90% chance that the last frost has passed, wait until Apr 25. Nearby ZIP codes are in USDA hardiness zone 8b.
- Apr 5Last spring frost (median)50% chance of 32°F after this date
- Apr 25Safer planting date10% chance of 32°F after this date
- Nov 10First fall frost (median)50% chance of 32°F by this date
- 217 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 6 | Apr 23 | May 9 |
| 32°F | Mar 13 | Apr 5 | Apr 25 |
| 28°F | Feb 16 | Mar 12 | Apr 8 |
| 24°F | Jan 15 | Feb 16 | Mar 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 |
|---|---|---|---|
| 36°F | Oct 13 | Oct 30 | Nov 14 |
| 32°F | Oct 21 | Nov 10 | Nov 27 |
| 28°F | Nov 1 | Nov 20 | Dec 9 |
| 24°F | Nov 10 | Dec 2 | Dec 26 |
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 | 166 days | 190 days | 212 days |
| 32°F | 190 days | 217 days | 247 days |
| 28°F | 217 days | 251 days | 279 days |
| 24°F | 250 days | 286 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 |
|---|---|---|---|
| 85640 | 8b | 15 to 20°F | 0 km |
| 85646 | 8b | 15 to 20°F | 6 km |
| 85645 | 8b | 15 to 20°F | 17 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 USC00028865, at 31.5678, -111.0497, elevation 996 m (3,267 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 60.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Nogales 6 N (15 km)
- Nogales Intl Airport (25 km)
- Santa Rita Exp. Range (29 km)
- Green Valley (37 km)
- Sonoita (39 km)
- Sasabe (48 km)
- Canelo 1 NW (49 km)
- Elgin 5 S (51 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.