Last updated: March 2, 2024
The weather in San Antonio, United States, during September is characterized by an average temperature of 27°C (80°F). Highs can soar to 37°C (100°F), while lows may dip to 16°C (60°F). Typically, the humidity level in San Antonio throughout September hovers around 65%.
Minimum temperature
Average temperature
Maximum temperature
Humidity
In September, San Antonio averages 117 mm (4.6 inches) of rainfall, typically over the course of 10 rainy days. The month enjoys an average of 12 hours 17 minutes of daylight, with the sun shining for approximately 9 hours 12 minutes each day. Additionally, there is a 61% probability of sunny days during this period.
Precipitation
Rainy days
Sunshine hours
Chance of sun
In September, the UV Index in San Antonio reaches a maximum of 11, indicating a level of VeryHigh exposure. The most intense UV radiation typically occurs between 13:00 and 15:00, during which unprotected skin may burn in as little as 15 minutes.
| 07:00 | 08:00 | 09:00 | 10:00 | 11:00 | 12:00 | 13:00 | 14:00 | 15:00 | 16:00 | 17:00 | 18:00 | 19:00 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UVI | 0 | 1 | 2 | 4 | 7 | 9 | 10 | 10 | 9 | 6 | 4 | 2 | 1 |
| Exposure | Low | Moderate | High | VeryHigh | High | Moderate | Low | ||||||
| Time to burn | 45 min | 30 min | 25 min | 15 min | 25 min | 30 min | 45 min | ||||||