In September, Flensburg typically sees daytime highs of 16.9°C and overnight lows around 9.2°C. Compared to the annual average high of 11.2°C, September runs +5.7°C.
September in Flensburg averages a daytime high of 16.9°C and an overnight low of 9.2°C.
September runs +5.7°C compared to Flensburg's annual average high of 11.2°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 16.9°C and cooler evenings around 9.2°C.