In September, Sundsvall typically sees daytime highs of 13.7°C and overnight lows around 5.8°C. Compared to the annual average high of 7.5°C, September runs +6.2°C.
September in Sundsvall averages a daytime high of 13.7°C and an overnight low of 5.8°C.
September runs +6.2°C compared to Sundsvall's annual average high of 7.5°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 13.7°C and cooler evenings around 5.8°C.