Today | Weather | Tuesday, April 7, 2026

Weather in San Mateo, California

05:03 AM
Now
Foggy Weather
52° F
Feels Like 46°
Precipitation 0 %
Wind 8 mph
Humidity 89 %
Today
Cloudy Weather
Day 66°
Night 52°
Precipitation 0 %
Wind 10 mph
UV Index (0 - 11+) 7

San Mateo Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (April 7, 2025)
Cloudy Weather

Day

66°

Night

52°

Wind

8 mph

UV Index

5

Precipitation

40 %

Air Quality in San Mateo

NOW
45 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 2.96 µg/m³
PM10 7.99 µg/m³
O3 0.048 ppm
NO2 0.2 ppb
SO2 0.3 ppb
CO 0.11 ppm
NH3 0 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.52.96 µg/m³
PM107.99 µg/m³
O394.56 µg/m³
NO20.47 µg/m³
SO20.79 µg/m³
CO127.54 µg/m³
NH30 µg/m³
NO0 µg/m³