San Antonio, TX 78207 Frost Dates
78207, near San Antonio, TX: the frost window
Typically, the last spring freeze lands around 02/25, roughly 181 days out. Fall's first freeze usually shows up around 11/28, roughly 277 days after the last spring frost.
San Antonio sits in USDA Zone 9a (20 to 25°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
San Antonio's growing season runs out in roughly 13 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
02/25 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/19 and only about 1 year in 10 sees frost after that.
San Antonio against the rest of the dataset
About 277 days separate San Antonio's last and first frost, putting it 4,939 of 40,283 ZIP codes nationally. Within TX, it ranks 772 of 2,558.
Learn more
Two guides worth reading on 78207: zone vs. frost date, on why Zone 9a and San Antonio's frost date answer different questions, and the frost range, on how to read the range around San Antonio's dates instead of trusting one.