Hourly Weather | Today Friday, June 5, 2026
San Mateo, California
2 PM
Cloudy Weather
75°
Feels Like 79°
0
Humidity: 45%
UV Index: 10
Wind: 15 mph
3 PM
Cloudy Weather
73°
Feels Like 75°
0
Humidity: 46%
UV Index: 8
Wind: 17 mph
4 PM
Cloudy Weather
72°
Feels Like 72°
0
Humidity: 48%
UV Index: 5
Wind: 18 mph
5 PM
Cloudy Weather
70°
Feels Like 68°
0
Humidity: 51%
UV Index: 3
Wind: 20 mph
6 PM
Cloudy Weather
68°
Feels Like 66°
0
Humidity: 52%
UV Index: 2
Wind: 20 mph
7 PM
Cloudy Weather
66°
Feels Like 63°
0
Humidity: 56%
UV Index: 1
Wind: 18 mph
8 PM
Cloudy Weather
64°
Feels Like 59°
0
Humidity: 60%
UV Index: 0
Wind: 15 mph
9 PM
Cloudy Night
61°
Feels Like 55°
0
Humidity: 65%
UV Index: 0
Wind: 14 mph
10 PM
Cloudy Night
61°
Feels Like 55°
0
Humidity: 68%
UV Index: 0
Wind: 14 mph
11 PM
Cloudy Night
59°
Feels Like 54°
0
Humidity: 70%
UV Index: 0
Wind: 13 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 4.48 µg/m³
  • PM10: 17.08 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.1 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.28 µg/m³
  • PM10: 16.48 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.1 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.1 µg/m³
  • PM10: 16.13 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.1 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
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.99 µg/m³
  • PM10: 16.07 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.1 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
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.96 µg/m³
  • PM10: 16.22 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.1 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
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 3.97 µg/m³
  • PM10: 16.32 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.2 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
39 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 4.11 µg/m³
  • PM10: 16.59 µg/m³
  • O3: 0.042 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.28 µg/m³
  • PM10: 16.87 µg/m³
  • O3: 0.041 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.36 µg/m³
  • PM10: 16.94 µg/m³
  • O3: 0.040 ppm
  • NO2: 0.2 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 4.23 µg/m³
  • PM10: 16.58 µg/m³
  • O3: 0.040 ppm
  • NO2: 0.3 ppb
  • SO2: 0.4 ppb
  • CO: 0.09 ppm

Health Recommendations:

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