In September, San Tan Valley typically sees daytime highs of 37.2°C and overnight lows around 20.1°C. Compared to the annual average high of 29.7°C, September runs +7.5°C.
September in San Tan Valley averages a daytime high of 37.2°C and an overnight low of 20.1°C.
September runs +7.5°C compared to San Tan Valley's annual average high of 29.7°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 37.2°C and cooler evenings around 20.1°C.