In September, Saint-Brieuc typically sees daytime highs of 19.1°C and overnight lows around 11.7°C. Compared to the annual average high of 14.1°C, September runs +5.0°C.
September in Saint-Brieuc averages a daytime high of 19.1°C and an overnight low of 11.7°C.
September runs +5.0°C compared to Saint-Brieuc's annual average high of 14.1°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 19.1°C and cooler evenings around 11.7°C.