Frost Dates for 78207 — San Antonio, Texas

Half of springs at San Antonio Incarnate Word, TX see their last 32°F night by February 25; only one in ten is past it by January 28, and one in ten still has one after March 19. Planting tender crops after March 5 leaves a 30% risk of a frost on them, after March 10 20%, and after March 19 10%. The 22 days between the even-odds date and the one-in-ten date is wider than at 63% of the 339 Texas stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by November 28 in half of years, as early as November 7 one year in ten, and holds off past December 21 one year in ten. A hard freeze of 28°F follows 17 days later, around December 15; in spring the one-in-ten date for 28°F is March 5, 14 days before the 32°F one. The freeze-free season lasts 277 days in a typical year, longer than at 76% of the 339 Texas stations; it reaches 313 days one year in ten and falls short of 249 one year in ten. On average 22 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 13 days longer, to about March 10, and return around November 16. Nights of 24°F, cold enough to damage hardier plants, come in 65% of winters and 16°F in 3%.

August is the warmest month at San Antonio Incarnate Word, TX, averaging 95°F by day and 74°F at night; January is the coldest at 63°F and 40°F. A freezing night is all but certain in January (a 90% chance or more). From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 71% of years and March still brings one in 40% of years.

Warmth for growing adds up to 7,164 growing degree days a year (base 50°F), more than at 72% of the 351 Texas stations. 43% of them (3,047) have built up by the end of June, and August adds the most, 1,076. Precipitation totals 34.0 inches a year, most in May (4.4") and least in February (1.9"); May to September bring 49% of it.

The nearest other station, San Antonio Kelly AFB, TX, 5 miles southwest of San Antonio, has a last frost 3 days earlier (February 22), a first frost 4 days later (December 2), a season 7 days longer.

Measurable snow is rare here: only 4 of 19 winters from 1991 to 2020 recorded 0.1 inch or more at San Antonio Incarnate Word, TX, 4.4 miles away, so there is no typical first-snow date to plan around.

ZIP 78207 is 4 miles from San Antonio Incarnate Word, TX, which stands at 700 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 11 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 78207 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°C) over 1991–2020; a zone describes winter lows, not frost dates.