In September, San Rafael typically sees daytime highs of 20.4°C and overnight lows around 11.9°C. Compared to the annual average high of 16.7°C, September runs +3.7°C.
September in San Rafael averages a daytime high of 20.4°C and an overnight low of 11.9°C.
September runs +3.7°C compared to San Rafael's annual average high of 16.7°C, ranking #1 of 12 months by warmth.
Plan for daytime highs near 20.4°C and cooler evenings around 11.9°C.