In September, Evanston typically sees daytime highs of 22.6°C and overnight lows around 14.1°C. Compared to the annual average high of 13.3°C, September runs +9.3°C.
September in Evanston averages a daytime high of 22.6°C and an overnight low of 14.1°C.
September runs +9.3°C compared to Evanston's annual average high of 13.3°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 22.6°C and cooler evenings around 14.1°C.