In September, Modesto typically sees daytime highs of 31.1°C and overnight lows around 13.5°C. Compared to the annual average high of 23.6°C, September runs +7.5°C.
September in Modesto averages a daytime high of 31.1°C and an overnight low of 13.5°C.
September runs +7.5°C compared to Modesto's annual average high of 23.6°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 31.1°C and cooler evenings around 13.5°C.