In September, Houston typically sees daytime highs of 31.8°C and overnight lows around 20.7°C. Compared to the annual average high of 26.2°C, September runs +5.6°C.
September in Houston averages a daytime high of 31.8°C and an overnight low of 20.7°C.
September runs +5.6°C compared to Houston's annual average high of 26.2°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 31.8°C and cooler evenings around 20.7°C.