Month-by-month travel weather

San Antonio September weather

San Antonio, United States · September

Some years see heavier early-fall rain events

Heat can linger, while rain events can vary. Keep plans flexible if forecasts shift.

September averages at a glance

Average low

around 21–23°C

Average high

around 33–35°C

Average precipitation

around 70–120 mm

Precip days

about 5–8 days

What to wear in September in San Antonio

Actual feel will change with wind and rain, but use the suggestions below to build a comfortable layered outfit.

  • Light clothing
  • Optional rain option

Travel tips for visiting San Antonio in September

  • If heavy rain is forecast, split errands and walks into shorter hops.

September weather in San Antonio — FAQ

Q. Does September cool down?

A. Gradually, but it can still feel very warm.

Explore San Antonio

These pages are connected so you can compare conditions and decide for yourself.

San Antonio September weather — averages & travel outfits | CityWeather | CityWeather