In September, Fairfield typically sees daytime highs of 28.6°C and overnight lows around 12.1°C. Compared to the annual average high of 21.5°C, September runs +7.0°C.
September in Fairfield averages a daytime high of 28.6°C and an overnight low of 12.1°C.
September runs +7.0°C compared to Fairfield's annual average high of 21.5°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 28.6°C and cooler evenings around 12.1°C.