San Antonio, Texas climate: Normal weather by month, frost dates and records

What is the weather like in San Antonio each month?

August is the warmest month, with normal highs of 96°F; January the coldest, with normal lows of 41°F. The most precipitation falls in May (4.40 in), the least in February (1.74 in).

Each month has its own page with the day-by-day normals, the month's records and its recent years:

• Jan
• Feb
• Mar
• Apr
• May
• Jun
• Jul
• Aug
• Sep
• Oct
• Nov
• Dec

When is the best weather to visit San Antonio?

Normal highs sit between 65°F and 85°F in February, March, April, October and November. Of those, April has the fewest days with rain (6).

That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.

When is the last frost in San Antonio?

In San Antonio, the last spring frost (32°F) comes after February 26 in half of years and after March 17 in one year in ten; the first autumn frost comes before November 28 in half of years and before November 7 in one year in ten.

Last spring frost, half of years after

February 261 year in 10 after March 17; 9 in 10 after January 29

First autumn frost, half of years before

November 281 year in 10 before November 7; 9 in 10 before December 22

NOAA puts the median frost-free season at 277 days, and the season without a hard freeze (28°F) at 311 days.

A hard freeze (28°F) comes after February 9 in half of springs and before December 13 in half of autumns.

The USDA's 2023 Plant Hardiness Zone Map puts San Antonio in zones 8b to 9a across its 60 ZIP code areas (8b in 78023, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, San Antonio's NOAA station is in zone 9a: the coldest night of a typical year reaches 24°F (30 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.

Frost dates for every NOAA station in Texas · Frost dates by ZIP code

What hardiness zone is each San Antonio ZIP code in?

The USDA's 2023 map gives each ZIP code area one zone. San Antonio's 60 ZIP code areas run from zone 8b to 9a: 3 in 8b and 57 in 9a. Each ZIP's frost dates are in the frost tool.

How hot and how cold does it get in San Antonio?

In a normal year in San Antonio, 122 days a year reach 90°F (18 of them 100°F or more), 14 nights fall to 32°F or colder and 81 days bring measurable precipitation.

Days at 90°F or more

122a normal year

Days at 100°F or more

18a normal year

Nights at 32°F or colder

14a normal year

Days that stay below freezing

fewer than 1high of 32°F or less

Days with 0.01 inch of precipitation

81a normal year

The highest temperature in San Antonio's official record (kept by the National Weather Service since 1885) is 111°F, on September 5, 2000; the lowest is 0°F, on January 31, 1949.

The wettest calendar year on that record is 1973, with 52.28 in; the snowiest season is 1984–85, with 15.9 inches.

How humid and windy is San Antonio, and how clear are its skies?

The summer (June-August) dew point averages 69°F. The muggiest month is June, with an average dew point of 70°F, above the 65°F at which most people call the air sticky; the driest air comes in December (38°F). April is the windiest month (9.8 mph on average), and September has the most clear or nearly clear hours (52%).

How sunny is San Antonio?

Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around San Antonio, 4.8 kWh per square metre a day. August is the sunniest month (88%) and February the cloudiest (69%). Among the 459 U.S. places of 50,000 or more, that ranks tied 210th (with 32 others) in sunshine.

How much heating and cooling does San Antonio need?

A normal year in San Antonio brings 1,438 heating degree days, 73% fewer than the median U.S. place (5,373), and 3,148 cooling degree days, 3.5 times the median (908). Two months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 7,392 growing degree days a year above 50°F.

Has San Antonio been warmer than normal lately?

2025 averaged 72.6°F, 3.0°F above the 1991-2020 normal of 69.6°F. 5 of the 5 complete years since 2021 ran warmer than the normal.

Over 127 complete years from 1885 to 2025, the station's annual mean temperature rose at a fitted 2.7°F per century (+0.15°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.

Which places near San Antonio share this climate record?

5 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.

• Timberwood Park, TX34,980 people · 11 mi N
• Castle Hills, TX3,931 people · 2 mi SW
• Shavano Park, TX3,807 people · 5 mi NW
• Hollywood Park, TX3,128 people · 4 mi N
• Hill Country Village, TX949 people · 3 mi N

What do San Antonio's other NOAA stations record?

4 more NOAA stations keep 1991-2020 normals in or near San Antonio. This page uses San Antonio International Airport; the others differ by site and elevation, and the linked ones have pages of their own:

Nearby and next

• San Antonio in OctoberThis month day by day, its records and recent years
• Texas climateThe statewide normals and every place in the state
• San Antonio Incarnate Word, TX5 miles from this station, 69.0°F a year
• San Antonio Kelly Air Force Base, TX12 miles from this station, 70.0°F a year
• Randolph AFB, TX12 miles from this station, 69.3°F a year
• San Antonio/Seaworld, TX15 miles from this station, 71.2°F a year
• Compare two placesMonth by month, side by side

Download these normals (CSV) · JSON · How these figures are made