Typically, San Antonio experiences a transition from summer to fall during September. This period is characterized by gradually decreasing temperatures, though daytime highs can still reach into the 90s Fahrenheit (low to mid 30s Celsius) early in the month. Overnight lows progressively cool from the 70s Fahrenheit (low 20s Celsius) to the 60s Fahrenheit (mid-teens Celsius). Rainfall amounts are generally lower than in previous months but can vary significantly year to year, with the possibility of occasional heavier downpours, especially during the early part of the month. Humidity levels also tend to decrease as the month progresses, providing a welcome respite from the summer’s mugginess.
Understanding the typical climatic conditions of this period is crucial for residents and visitors alike. Planning outdoor activities, choosing appropriate attire, and even making travel arrangements can be significantly impacted by the expected temperature and precipitation patterns. Historical weather data for San Antonio in September provides valuable insights for long-term planning and understanding the potential impacts on local businesses, particularly those related to tourism and agriculture.