San Antonio, TX climate
San Antonio has warm winters and hot summers. A typical July afternoon reaches 95°, a January night drops to 41°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in San Antonio feels like
Winter
Spring
Summer
Fall
San Antonio weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 64° | 41° | 1.9" | 0 | 8 | 0 | 48° – 58° |
| February | 68° | 45° | 1.8" | 0 | 10 | 0 | 49° – 64° |
| March | 74° | 52° | 2.4" | 0 | 9 | 0 | 57° – 68° |
| April | 81° | 58° | 2.4" | 0 | 6 | 0 | 64° – 76° |
| May | 87° | 66° | 4.0" | 0 | 8 | 0 | 72° – 80° |
| June | 93° | 72° | 3.4" | 0 | 7 | 0 | 79° – 86° |
| July | 95° | 74° | 2.3" | 0 | 7 | 0 | 80° – 88° |
| August | 97° | 74° | 2.4" | 0 | 4 | 0 | 81° – 89° |
| September | 91° | 69° | 3.6" | 0 | 8 | 0 | 76° – 85° |
| October | 83° | 60° | 3.4" | 0 | 8 | 0 | 68° – 76° |
| November | 72° | 50° | 2.2" | 0 | 7 | 0 | 56° – 67° |
| December | 65° | 42° | 1.9" | 0.1" | 8 | 0 | 47° – 57° |
| Year | 81° | 58° | 31.6" | 0.1" | 89 | 0 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in San Antonio
San Antonio gets 32 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 89 days a year.
About 277 frost-free days a year
In half of years the last 32° night comes by February 25 and the first one by November 28. That leaves about 277 frost-free days for gardens, longer than 93% of U.S. towns.
Heating and cooling a home in San Antonio
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In San Antonio, 34% of that work is heating and 66% is cooling, so air conditioning is the bigger bill.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
San Antonio and its neighbors
San Antonio borders 12 towns with climate data. January nights across them vary by 1.9°. Fair Oaks Ranch has the coldest January nights (39°) and Von Ormy the hottest July afternoons (97°). San Antonio’s January low is 41° and its July high 95°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How San Antonio compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in San Antonio averaged 1.0° warmer than the 1900s. The biggest change is in February (+1.9°). The shift is smaller than in 72% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at San Antonio’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 49° to 64°. June is the most reliable, staying within 8°.
Common questions about San Antonio’s climate
What is the coldest month in San Antonio?
January, with a typical high of 64° and a low of 41°.
What is the hottest month in San Antonio?
August, with a typical high of 97° and a low of 74°. About 112 days a year reach 90°.
How much snow does San Antonio get?
Almost none. A normal year brings 0.1 inches.
When is the first frost in San Antonio?
In half of years the first 32° night comes by November 28, and the last spring frost by February 25.
What is the rainiest month in San Antonio?
May, with 4.0 inches of rain and melted snow. The year totals 32 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for San Antonio itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at San Antonio Incarnate Word, TX (3 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.