In May, San Mateo typically sees daytime highs of 33.0°C and overnight lows around 24.6°C. Compared to the annual average high of 30.4°C, May runs +2.5°C.
May in San Mateo averages a daytime high of 33.0°C and an overnight low of 24.6°C.
May runs +2.5°C compared to San Mateo's annual average high of 30.4°C, ranking #1 of 12 months by warmth.
Plan for daytime highs near 33.0°C and cooler evenings around 24.6°C.