In September, Watford typically sees daytime highs of 18.2°C and overnight lows around 10.1°C. Compared to the annual average high of 13.4°C, September runs +4.8°C.
September in Watford averages a daytime high of 18.2°C and an overnight low of 10.1°C.
September runs +4.8°C compared to Watford's annual average high of 13.4°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 18.2°C and cooler evenings around 10.1°C.