In October, San Mateo typically sees daytime highs of 20.1°C and overnight lows around 10.3°C. Compared to the annual average high of 17.7°C, October runs +2.5°C.
October in San Mateo averages a daytime high of 20.1°C and an overnight low of 10.3°C.
October runs +2.5°C compared to San Mateo's annual average high of 17.7°C, ranking #4 of 12 months by warmth.
Plan for daytime highs near 20.1°C and cooler evenings around 10.3°C.