Thorsby, AL 35171 Frost Dates
Thorsby, AL: when does the frost end?
Around 03/21 is the usual last spring frost, about 205 days away. Fall's first freeze usually shows up around 11/11, roughly 235 days after the last spring frost.
Thorsby sits in USDA Zone 8a (10 to 15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 11 weeks until Thorsby's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 03/21 isn't a guarantee
03/21 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/10 and only about 1 year in 10 sees frost after that.
Thorsby against the rest of the dataset
At roughly 235 frost-free days, Thorsby places 9,614 of 40,283 ZIP codes in this dataset. Within AL, it ranks 429 of 809.
Learn more
Before leaning on 35171's figures: local microclimates explains what one yard in Thorsby can differ from the 35171 normal, while zone vs. frost date explains why Zone 8a and Thorsby's frost date answer different questions.