In September, Lille typically sees daytime highs of 19.5°C and overnight lows around 9.9°C. Compared to the annual average high of 13.8°C, September runs +5.7°C.
September in Lille averages a daytime high of 19.5°C and an overnight low of 9.9°C.
September runs +5.7°C compared to Lille's annual average high of 13.8°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 19.5°C and cooler evenings around 9.9°C.