In September, Brno typically sees daytime highs of 19.6°C and overnight lows around 9.4°C. Compared to the annual average high of 13.1°C, September runs +6.6°C.
September in Brno averages a daytime high of 19.6°C and an overnight low of 9.4°C.
September runs +6.6°C compared to Brno's annual average high of 13.1°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 19.6°C and cooler evenings around 9.4°C.