San Antonio weather in August
In August, San Antonio has an average high of 36 °C97 °F and an average low of 24 °C76 °F, with about 62 mm2.4 in of precipitation. August is the warmest month of the year and ranks 7th for precipitation.
How August compares with other months
Compared with July, August is 0.7 °C1.2 °F warmer on average and drier by 9 mm0.4 in. Compared with September, August is 3.6 °C6.5 °F warmer on average and drier by 34 mm1.3 in. Daylight lasts about 13.2 hours around the middle of the month. Average relative humidity is 61% and the average cloud amount 41%.
Is August a good time to visit San Antonio?
August is not among the most comfortable months by our comfort score: it is hot (average high 36 °C97 °F) and it is fairly wet (62 mm2.4 in). The most comfortable months in San Antonio are February–April and October–December.
What to wear in August
For San Antonio in August, pack very light, breathable clothing, a sun hat and plenty of water.
August in nearby places
| Place | High °C°F | Low °C°F | Precip. mmin |
|---|---|---|---|
| San Antonio | 3697 | 2476 | 622.4 |
| Austin | 3798 | 2476 | 632.5 |
| Killeen | 3697 | 2474 | 612.4 |
| Corpus Christi | 3494 | 2578 | 552.2 |
| Piedras Negras | 38100 | 2577 | 421.7 |
| Ciudad Acuña | 3799 | 2678 | 431.7 |
| Nuevo Laredo | 3799 | 2577 | 441.7 |
| College Station | 3696 | 2475 | 903.5 |
| Waco | 3697 | 2476 | 652.6 |
Nearby places that are more than 1 °C1.8 °F warmer in August: Piedras Negras and Ciudad Acuña.
Other months in San Antonio
- January17 °C63 °F / 5 °C40 °F
- February20 °C68 °F / 6 °C44 °F
- March24 °C76 °F / 11 °C51 °F
- April29 °C84 °F / 15 °C59 °F
- May32 °C89 °F / 19 °C67 °F
- June35 °C95 °F / 23 °C73 °F
- July36 °C96 °F / 24 °C75 °F
- August36 °C97 °F / 24 °C76 °F
- September32 °C90 °F / 21 °C70 °F
- October28 °C83 °F / 16 °C60 °F
- November23 °C73 °F / 10 °C50 °F
- December18 °C64 °F / 5 °C42 °F
Frequently asked questions
How warm is San Antonio in August?
In August the average high in San Antonio is 36 °C (97 °F) and the average low is 24 °C (76 °F).
Does it rain a lot in San Antonio in August?
On average about 62 mm (2.4 in) of precipitation falls in August; it ranks 7th of the 12 months.
Is August the warmest month in San Antonio?
Yes. August is the warmest month in San Antonio. The coldest month is January, with an average low of 5 °C (40 °F).
How long is the day in San Antonio in August?
In the middle of August the day in San Antonio lasts about 13.2 hours from sunrise to sunset. The value is calculated from the position of the city and the sun.
How humid is San Antonio in August?
The average relative humidity in August is about 61%. This is a long-term average for the whole day.
How cloudy is San Antonio in August?
On average about 41% of the sky is covered by cloud in August. This is the mean cloud amount from satellite data, not the number of sunny days.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 302 m, while San Antonio lies at about 198 m. Temperatures on this page were therefore adjusted by +0.7 °C1.2 °F using the standard lapse rate of 6.5 °C per 1,000 m.