Mountain Brook, AL 35223 Frost Dates
35223, near Mountain Brook, AL: the frost window
Typically, the last spring freeze lands around 03/21, roughly 205 days out. Fall's first freeze usually shows up around 11/11, roughly 236 days after the last spring frost.
Mountain Brook sits in USDA Zone 8b (15 to 20°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
Mountain Brook's growing season runs out in roughly 11 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Mountain Brook's last frost
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 04/08 and only about 1 year in 10 sees frost after that.
Mountain Brook against the rest of the dataset
Mountain Brook's growing season runs about 236 days, ranking 9,327 of 40,283 US ZIP codes measured here, longest to shortest. Within AL, it ranks 372 of 809.
Learn more
Two guides worth reading on 35223: the frost range, on how to read the range around Mountain Brook's dates instead of trusting one, and local microclimates, on what one yard in Mountain Brook can differ from the 35223 normal.