In September, Fairfield typically sees daytime highs of 23.6°C and overnight lows around 12.4°C. Compared to the annual average high of 15.8°C, September runs +7.9°C.
September in Fairfield averages a daytime high of 23.6°C and an overnight low of 12.4°C.
September runs +7.9°C compared to Fairfield's annual average high of 15.8°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 23.6°C and cooler evenings around 12.4°C.