San Mateo, California Weather:
Friday, September 18, 2026
Cloudy Weather
Day 77°
Night 59°
Precipitation 1 %
Wind 7 mph
UV Index (0 - 11+) 6
Weather Forecast History
Last Year's Weather on This Day (September 18, 2025)
Rainy Weather

Day

75°

Night

63°

Wind

6 mph

Precipitation

92 %