Hourly Weather | Today Thursday, October 30, 2025
San Mateo, California
12 PM
Cloudy Weather
63°
Feels Like 66°
0
Humidity: 76%
Wind: 8 mph
UV Index: 3
1 PM
Cloudy Weather
64°
Feels Like 66°
0
Humidity: 70%
Wind: 8 mph
UV Index: 4
2 PM
Cloudy Weather
66°
Feels Like 68°
0
Humidity: 66%
Wind: 9 mph
UV Index: 3
3 PM
Cloudy Weather
66°
Feels Like 66°
0
Humidity: 67%
Wind: 9 mph
UV Index: 3
4 PM
Cloudy Weather
64°
Feels Like 64°
0
Humidity: 69%
Wind: 9 mph
UV Index: 2
5 PM
Cloudy Weather
63°
Feels Like 63°
0
Humidity: 72%
Wind: 9 mph
UV Index: 1
6 PM
Cloudy Weather
61°
Feels Like 57°
0
Humidity: 77%
Wind: 9 mph
UV Index: 0
7 PM
Cloudy Night
61°
Feels Like 57°
0
Humidity: 79%
Wind: 8 mph
UV Index: 0
8 PM
Cloudy Night
57°
Feels Like 54°
0
Humidity: 83%
Wind: 8 mph
UV Index: 0
9 PM
Cloudy Night
55°
Feels Like 52°
0
Humidity: 91%
Wind: 8 mph
UV Index: 0
10 PM
Cloudy Night
52°
Feels Like 48°
0
Humidity: 99%
Wind: 8 mph
UV Index: 0
11 PM
Cloudy Night
52°
Feels Like 48°
0
Humidity: 98%
Wind: 7 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

12 PM
39 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.55 µg/m³
  • PM10: 32.15 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.4 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

1 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.8 µg/m³
  • PM10: 32.97 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

2 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.91 µg/m³
  • PM10: 33.04 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

3 PM
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.8 µg/m³
  • PM10: 32.42 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

4 PM
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.53 µg/m³
  • PM10: 31.38 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

5 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.17 µg/m³
  • PM10: 30.13 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

6 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 7.68 µg/m³
  • PM10: 28.5 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

7 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 7.26 µg/m³
  • PM10: 27.58 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

8 PM
42 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 6.86 µg/m³
  • PM10: 26.92 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

9 PM
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 6.58 µg/m³
  • PM10: 26.34 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

10 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 6.46 µg/m³
  • PM10: 25.97 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

11 PM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 6.44 µg/m³
  • PM10: 25.57 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.3 ppb
  • SO2: 0.3 ppb
  • CO: 0.09 ppm

Health Recommendations:

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