Frost dates for Alabaster Shelby Co Airport, AL
At Alabaster Shelby Co Airport, the median last spring frost (32°F) is Mar 12 and the median first fall frost is Nov 16, for a typical growing season of 248 days. For a 90% chance that the last frost has passed, wait until Mar 31. Nearby ZIP codes are in USDA hardiness zones 8a to 8b.
- Mar 12Last spring frost (median)50% chance of 32°F after this date
- Mar 31Safer planting date10% chance of 32°F after this date
- Nov 16First fall frost (median)50% chance of 32°F by this date
- 248 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 | Mar 7 | Mar 27 | Apr 14 |
| 32°F | Feb 20 | Mar 12 | Mar 31 |
| 28°F | Jan 31 | Feb 27 | Mar 17 |
| 24°F | Jan 11 | Feb 7 | Mar 6 |
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 23 | Nov 4 | Nov 21 |
| 32°F | Nov 1 | Nov 16 | Dec 4 |
| 28°F | Nov 10 | Dec 1 | Dec 28 |
| 24°F | Nov 24 | Dec 22 | Jan 16 |
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 | 199 days | 221 days | 248 days |
| 32°F | 224 days | 248 days | 277 days |
| 28°F | 250 days | 278 days | 311 days |
| 24°F | 277 days | 312 days | 343 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 97% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 35007 | 8b | 15 to 20°F | 5 km |
| 35040 | 8b | 15 to 20°F | 10 km |
| 35115 | 8b | 15 to 20°F | 11 km |
| 35051 | 8b | 15 to 20°F | 17 km |
| 35035 | 8a | 10 to 15°F | 23 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 USW00053864, at 33.1783, -86.7817, elevation 172 m (565 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 43.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Helena (12 km)
- Thorsby Exp. Station (30 km)
- Bessemer 3 WSW (32 km)
- Clanton 2 NE (40 km)
- Childersburg Water Plant (42 km)
- Birmingham Airport (43 km)
- Clanton (44 km)
- Sylacauga 4 NE (53 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.