In September, San Jose typically sees daytime highs of 30.4°C and overnight lows around 23.4°C. Compared to the annual average high of 31.0°C, September runs -0.6°C.
September in San Jose averages a daytime high of 30.4°C and an overnight low of 23.4°C.
September runs -0.6°C compared to San Jose's annual average high of 31.0°C, ranking #9 of 12 months by warmth.
Plan for daytime highs near 30.4°C and cooler evenings around 23.4°C.