Hourly Weather | Today Thursday, September 11, 2025
San Mateo, California
8 PM
Cloudy Night
68°
Feels Like 64°
0
Humidity: 70%
Wind: 10 mph
UV Index: 0
9 PM
Cloudy Night
68°
Feels Like 64°
0
Humidity: 72%
Wind: 9 mph
UV Index: 0
10 PM
Cloudy Night
64°
Feels Like 63°
0
Humidity: 79%
Wind: 9 mph
UV Index: 0
11 PM
Cloudy Night
64°
Feels Like 63°
0
Humidity: 83%
Wind: 8 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

8 PM
45 AQI
Good air quality Dominant pollutant: pm25
Details

Pollutant Concentrations:

  • PM2.5: 8.74 µg/m³
  • PM10: 11.54 µg/m³
  • O₃: 31.33 ppb
  • NO₂: 4.61 ppb
  • SO₂: 0.64 ppb
  • CO: 139.39 ppb

Health Recommendations:

With this level of air quality, you have no limitations. Enjoy the outdoors

9 PM
45 AQI
Good air quality Dominant pollutant: pm25
Details

Pollutant Concentrations:

  • PM2.5: 9.39 µg/m³
  • PM10: 12.38 µg/m³
  • O₃: 29.93 ppb
  • NO₂: 5.27 ppb
  • SO₂: 0.73 ppb
  • CO: 140.41 ppb

Health Recommendations:

With this level of air quality, you have no limitations. Enjoy the outdoors

10 PM
45 AQI
Good air quality Dominant pollutant: pm25
Details

Pollutant Concentrations:

  • PM2.5: 10.10 µg/m³
  • PM10: 13.29 µg/m³
  • O₃: 28.54 ppb
  • NO₂: 5.92 ppb
  • SO₂: 0.81 ppb
  • CO: 141.42 ppb

Health Recommendations:

With this level of air quality, you have no limitations. Enjoy the outdoors

11 PM
46 AQI
Good air quality Dominant pollutant: pm25
Details

Pollutant Concentrations:

  • PM2.5: 10.44 µg/m³
  • PM10: 13.80 µg/m³
  • O₃: 27.15 ppb
  • NO₂: 6.57 ppb
  • SO₂: 0.90 ppb
  • CO: 142.43 ppb

Health Recommendations:

With this level of air quality, you have no limitations. Enjoy the outdoors