San Antonio weather in August
August in San Antonio: sweltering, a little rain, with clean air — a fair time to visit.
#12 of 12 months in San Antonio · #513 of 604 destinations to visit in August · comfort 57/100 (tier D)
Updated June 2026 · climate normals from ERA5 reanalysis
San Antonio climate normals — August
| Daytime high | 37°C / 98°F | 🔥 sweltering |
|---|---|---|
| Nighttime low | 26°C / 78°F | |
| Feels like (high) | 39°C / 102°F | |
| Rainfall | 34 mm / 1.4 in | 🌦 some rain |
| Rainy days | 6 days | |
| Humidity | 58% | 🍃 comfortable |
| Dew point | 20°C / 69°F | |
| Sunshine | 11.8 h/day | |
| Daylight | 13.2 h | |
| Wind | 17 km/h / 11 mph | |
| Air quality (US AQI) | 47 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
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San Antonio in August — FAQ
- Is August a good time to visit San Antonio?
- August in San Antonio: sweltering, a little rain, with clean air — a fair time to visit. It ranks #12 of 12 months for San Antonio on SeasonMap's comfort score (57/100).
- What is the weather like in San Antonio in August?
- In August, San Antonio averages a daily high of 36.5°C and a low of 25.6°C, with about 34.3 mm of rain over roughly 6 rainy days.
- What is the air quality in San Antonio in August?
- San Antonio has a mean US Air Quality Index of about 47 in August.