San Antonio, TX weather in August
August in San Antonio: hot, oppressively humid and mostly dry. Highs 96°F, lows 75°F, about 5 wet days. This is the peak of the warm season in San Antonio. Midday heat is the main thing to plan around.
- Normal high
- 96°F
- Normal low
- 75°F
- Wet days
- 5
- 2.1 in total
- Muggy days
- 28
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 97°F | 94°F |
| Normal low | 75°F | 73°F |
| Chance of a wet day | 14% | 20% |
| Sunrise / sunset | 6:54 am / 8:26 pm | 7:11 am / 7:57 pm |
| Daylight | 13.5 h | 12.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Central Time).
A typical August day
- 6 am76°Fdew point 73°F
- 9 am83°Fdew point 73°F
- Noon91°Fdew point 69°F
- 3 pm95°Fdew point 66°F
- 6 pm93°Fdew point 66°F
- 9 pm85°Fdew point 69°F
NOAA hourly normals (local standard time) from San Antonio Kelly AFB (6 mi away); average wind 7 mph.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F0 of 31
- Hot dayshigh 90°F or more29 of 31
- Muggy daysdaily mean dew point 65°F or more28 of 31
- Wet daysat least 0.01 in of rain or melted snow5 of 31
- Notable rainat least 0.10 in3 of 31
- Freezing nightslow 32°F or below0 of 31
Average days per August, counted from daily records for each year 1991-2020.
Rain in August
Normal precipitation is 2.1 in; a dry August brings about 0.3 in and a wet one about 2.8 in (25th and 75th percentiles). About 1 day brings half an inch or more, and about 1 an inch or more.
How August varies from year to year
- Warmest August, 1991-20202011: average high 102°F
- Coolest August2007: average high 92°F
- Wettest August2001: 7.8 in
- Driest August1993: 0.01 in
- Highest reading110°F (August 28, 2011)
- Lowest reading61°F (August 29, 1992)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
August compared with July and September
| July | August | September | |
|---|---|---|---|
| Normal high | 95°F | 96°F | 90°F |
| Normal low | 75°F | 75°F | 70°F |
| Wet days | 5 | 5 | 7 |
| Comfortable days | 0 | 0 | 1 |
| Daylight | 13.8 h | 13.2 h | 12.3 h |
Highs change by +1°F from July and -6°F into September.
Nearby alternatives in August
- Cooler: South Padre Island, TX243 mi · high 90°F · 6 wet days
How San Antonio ranks in August
- Normal high41st warmest of 378 cities; 17th of 38 in Texas
- Wet days88th driest of 378
- Comfortable days337th most of 341
What to pack for San Antonio in August
- Light, breathable clothing – highs near 96°F and about 28 muggy days
Heating and cooling
August has 0 heating degree days and 634 cooling degree days (base 65°F), 14% of the year's total heating and cooling demand.
Questions
How hot is San Antonio in August?
The normal high is 96°F and the normal low is 75°F. From 1991 to 2020 the hottest August reading was 110°F (August 28, 2011).
Does it rain a lot in San Antonio in August?
About 5 days in August have at least 0.01 in of precipitation, and the normal total is 2.2 in. The wettest August in 1991-2020 was in 2001 (7.8 in); the driest was in 1993 (0.01 in).
Is August a good time to visit San Antonio?
August ranks 12th of 12 months on our comfort score for San Antonio (34 out of 100). It has almost no comfortable days and about 29 days at 90°F or hotter. The best months are February, March and November.
Where the numbers come from
- Temperature, rain, snowfall, snow depth and frost dates: San Antonio Intl Airport (USW00012921), 8.3 mi N of the city center, 789 ft (140 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour: San Antonio Kelly AFB (USW00012909), 6.1 mi WSW of the city center, 682 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: San Antonio International Airport (722530-12921), 8.3 mi N of the city center, 799 ft (150 ft higher than the city). Hourly observations, 1991-2020.
- Not available for this location: cloud cover (no station close enough or similar enough in elevation).