Temperature for September
In San Antonio, TX during September the average high temperature is 90.3°F. The hottest day on record was September 6, 2000 when the temperature hit 111.0°F.

In San Antonio, TX during September the average high temperature is 90.3°F. The hottest day on record was September 6, 2000 when the temperature hit 111.0°F.
In September the average monthly rainfall in San Antonio, TX is 2.31 inches with rain usually falling on between 7 and 8 days. 1947 was the driest September with only 0.00 inches of rain falling, and 1973 was the wettest September with 12.97 inches of rain. The wettest single day in September was 27 September 1973 when 7.28 inches of rain fell.
In September it usually snows on between 0 and 1 days. There are thunderstorms on between 3 and 4 days in September.