In September, Folsom typically sees daytime highs of 31.2°C and overnight lows around 13.5°C. Compared to the annual average high of 23.3°C, September runs +7.9°C.
September in Folsom averages a daytime high of 31.2°C and an overnight low of 13.5°C.
September runs +7.9°C compared to Folsom's annual average high of 23.3°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 31.2°C and cooler evenings around 13.5°C.