In September, Ann Arbor typically sees daytime highs of 23.4°C and overnight lows around 10.6°C. Compared to the annual average high of 14.4°C, September runs +9.0°C.
September in Ann Arbor averages a daytime high of 23.4°C and an overnight low of 10.6°C.
September runs +9.0°C compared to Ann Arbor's annual average high of 14.4°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 23.4°C and cooler evenings around 10.6°C.