In September, San Clemente typically sees daytime highs of 26.2°C and overnight lows around 16.2°C. Compared to the annual average high of 22.2°C, September runs +4.0°C.
September in San Clemente averages a daytime high of 26.2°C and an overnight low of 16.2°C.
September runs +4.0°C compared to San Clemente's annual average high of 22.2°C, ranking #2 of 12 months by warmth.
Plan for daytime highs near 26.2°C and cooler evenings around 16.2°C.