Hourly Weather | Today Monday, April 6, 2026
San Mateo, California
6 AM
Cloudy Night
52°
Feels Like 48°
0
Humidity: 90%
UV Index: 0
Wind: 7 mph
7 AM
Cloudy Weather
52°
Feels Like 48°
0
Humidity: 91%
UV Index: 0
Wind: 7 mph
8 AM
Cloudy Weather
54°
Feels Like 54°
0
Humidity: 88%
UV Index: 1
Wind: 7 mph
9 AM
Cloudy Weather
55°
Feels Like 57°
0
Humidity: 80%
UV Index: 2
Wind: 7 mph
10 AM
Cloudy Weather
59°
Feels Like 63°
0
Humidity: 72%
UV Index: 4
Wind: 8 mph
11 AM
Cloudy Weather
63°
Feels Like 66°
0
Humidity: 66%
UV Index: 5
Wind: 8 mph
12 PM
Cloudy Weather
64°
Feels Like 70°
0
Humidity: 61%
UV Index: 6
Wind: 9 mph
1 PM
Cloudy Weather
66°
Feels Like 72°
0
Humidity: 56%
UV Index: 7
Wind: 9 mph
2 PM
Cloudy Weather
66°
Feels Like 72°
0
Humidity: 53%
UV Index: 6
Wind: 10 mph
3 PM
Cloudy Weather
68°
Feels Like 70°
0
Humidity: 51%
UV Index: 5
Wind: 12 mph
4 PM
Cloudy Weather
66°
Feels Like 66°
0
Humidity: 54%
UV Index: 4
Wind: 13 mph
5 PM
Cloudy Weather
64°
Feels Like 63°
0
Humidity: 56%
UV Index: 2
Wind: 13 mph
6 PM
Cloudy Weather
63°
Feels Like 61°
0
Humidity: 59%
UV Index: 1
Wind: 12 mph
7 PM
Cloudy Weather
61°
Feels Like 55°
0
Humidity: 64%
UV Index: 0
Wind: 12 mph
8 PM
Cloudy Night
57°
Feels Like 54°
0
Humidity: 71%
UV Index: 0
Wind: 10 mph
9 PM
Cloudy Night
55°
Feels Like 52°
0
Humidity: 77%
UV Index: 0
Wind: 9 mph
10 PM
Cloudy Night
54°
Feels Like 50°
0
Humidity: 79%
UV Index: 0
Wind: 9 mph
11 PM
Cloudy Night
55°
Feels Like 52°
0
Humidity: 79%
UV Index: 0
Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

6 AM
50 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.58 µg/m³
  • PM10: 13.42 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

7 AM
49 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.7 µg/m³
  • PM10: 13.91 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

8 AM
48 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.76 µg/m³
  • PM10: 14.12 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

9 AM
48 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.77 µg/m³
  • PM10: 14.07 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

10 AM
48 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.77 µg/m³
  • PM10: 13.98 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.4 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

11 AM
49 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.73 µg/m³
  • PM10: 13.69 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.3 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.66 µg/m³
  • PM10: 13.3 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.56 µg/m³
  • PM10: 12.84 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.45 µg/m³
  • PM10: 12.36 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.26 µg/m³
  • PM10: 11.73 µg/m³
  • O3: 0.054 ppm
  • NO2: 0.1 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4 µg/m³
  • PM10: 11.01 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.1 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.69 µg/m³
  • PM10: 10.23 µg/m³
  • O3: 0.053 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3.31 µg/m³
  • PM10: 9.28 µg/m³
  • O3: 0.052 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 3 µg/m³
  • PM10: 8.51 µg/m³
  • O3: 0.051 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.75 µg/m³
  • PM10: 7.93 µg/m³
  • O3: 0.050 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.57 µg/m³
  • PM10: 7.51 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.47 µg/m³
  • PM10: 7.25 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 2.38 µg/m³
  • PM10: 7.05 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.3 ppb
  • CO: 0.11 ppm

Health Recommendations:

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