In September, Sint-Niklaas typically sees daytime highs of 19.6°C and overnight lows around 10.3°C. Compared to the annual average high of 14.1°C, September runs +5.5°C.
September in Sint-Niklaas averages a daytime high of 19.6°C and an overnight low of 10.3°C.
September runs +5.5°C compared to Sint-Niklaas's annual average high of 14.1°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 19.6°C and cooler evenings around 10.3°C.