In September, Alkmaar typically sees daytime highs of 17.5°C and overnight lows around 11.9°C. Compared to the annual average high of 12.0°C, September runs +5.5°C.
September in Alkmaar averages a daytime high of 17.5°C and an overnight low of 11.9°C.
September runs +5.5°C compared to Alkmaar's annual average high of 12.0°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 17.5°C and cooler evenings around 11.9°C.