In October, Castro Valley typically sees daytime highs of 22.8°C and overnight lows around 10.6°C. Compared to the annual average high of 20.0°C, October runs +2.8°C.
October in Castro Valley averages a daytime high of 22.8°C and an overnight low of 10.6°C.
October runs +2.8°C compared to Castro Valley's annual average high of 20.0°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 22.8°C and cooler evenings around 10.6°C.