Last spring frost
Mar 21
Frost Dates for Thorsby, AL
First fall frost
Nov 11
Growing season
235 days
Hardiness zone
8a
In an average year around Thorsby, AL, the last spring frost (32°F) is about Mar 21 and the first fall frost is about Nov 11, giving roughly a 235-day growing season. To be safe most years, wait until Feb 28 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Apr 23 | Apr 5 | Mar 17 |
| Freeze (32°F) | Apr 10 | Mar 21 | Feb 28 |
| Hard (28°F) | Mar 26 | Mar 7 | Feb 15 |
| Severe (24°F) | Mar 16 | Feb 22 | Jan 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 17 | Apr 13 | Apr 10 | Apr 5 | Apr 2 | Mar 31 | Mar 24 | Mar 17 |
| 32°F | Apr 10 | Apr 3 | Mar 30 | Mar 25 | Mar 21 | Mar 17 | Mar 13 | Mar 7 | Feb 28 |
| 28°F | Mar 26 | Mar 19 | Mar 15 | Mar 12 | Mar 7 | Mar 3 | Feb 28 | Feb 22 | Feb 15 |
| 24°F | Mar 16 | Mar 10 | Mar 4 | Feb 28 | Feb 22 | Feb 16 | Feb 9 | Feb 3 | Jan 28 |
| 20°F | Mar 7 | Feb 27 | Feb 18 | Feb 10 | Feb 5 | Jan 31 | Jan 27 | Jan 18 | Jan 7 |
| 16°F | Feb 23 | Feb 10 | Feb 2 | Jan 31 | Jan 24 | Jan 19 | Jan 13 | Jan 7 | Dec 31 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 19 | Nov 1 | Nov 15 |
| Freeze (32°F) | Oct 29 | Nov 11 | Dec 1 |
| Hard (28°F) | Nov 5 | Nov 25 | Dec 21 |
| Severe (24°F) | Nov 17 | Dec 10 | Jan 10 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 19 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 15 |
| 32°F | Oct 29 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 19 | Nov 25 | Dec 1 |
| 28°F | Nov 5 | Nov 11 | Nov 16 | Nov 20 | Nov 25 | Nov 30 | Dec 3 | Dec 8 | Dec 21 |
| 24°F | Nov 17 | Nov 24 | Dec 1 | Dec 5 | Dec 10 | Dec 16 | Dec 25 | Jan 1 | Jan 10 |
| 20°F | Dec 1 | Dec 7 | Dec 15 | Dec 24 | Dec 30 | Jan 2 | Jan 8 | Jan 16 | Jan 30 |
| 16°F | Dec 13 | Dec 25 | Jan 1 | Jan 3 | Jan 8 | Jan 13 | Jan 19 | Jan 26 | Feb 6 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Thorsby Exp Stn, Al, about 5.5 miles away@if(!empty($station['elevation_ft'])), at 680 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Thorsby, AL?
On average, the last spring frost (32°F) around Thorsby, AL is about Mar 21. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 28.
When is the first frost in the fall?
The first fall frost around Thorsby, AL typically arrives about Nov 11. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Mar 21 on average, or Feb 28 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 235 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 35171 Planting calendar → Alabama frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026