Hourly Weather | Today Monday, September 14, 2026
St. Louis, Missouri
3 PM
Cloudy Weather
88°
Feels Like 88°
0
Humidity: 39%
UV Index: 4
Wind: 15 mph
4 PM
Cloudy Weather
88°
Feels Like 88°
0
Humidity: 40%
UV Index: 3
Wind: 15 mph
5 PM
Cloudy Weather
88°
Feels Like 86°
0
Humidity: 42%
UV Index: 2
Wind: 15 mph
6 PM
Cloudy Weather
84°
Feels Like 82°
0
Humidity: 47%
UV Index: 1
Wind: 14 mph
7 PM
Cloudy Weather
82°
Feels Like 81°
0
Humidity: 52%
UV Index: 0
Wind: 14 mph
8 PM
Cloudy Night
81°
Feels Like 79°
0
Humidity: 59%
UV Index: 0
Wind: 7 mph
9 PM
Cloudy Night
79°
Feels Like 77°
0
Humidity: 66%
UV Index: 0
Wind: 8 mph
10 PM
Cloudy Night
75°
Feels Like 75°
0
Humidity: 71%
UV Index: 0
Wind: 8 mph
11 PM
Cloudy Night
73°
Feels Like 73°
0
Humidity: 75%
UV Index: 0
Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

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

Pollutant Concentrations:

  • PM2.5: 7.29 µg/m³
  • PM10: 7.85 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.6 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 7.43 µg/m³
  • PM10: 7.96 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.2 ppb
  • SO2: 0.6 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 7.9 µg/m³
  • PM10: 8.41 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.3 ppb
  • SO2: 0.6 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 8.57 µg/m³
  • PM10: 9.11 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.4 ppb
  • SO2: 0.6 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 9.22 µg/m³
  • PM10: 9.79 µg/m³
  • O3: 0.049 ppm
  • NO2: 0.6 ppb
  • SO2: 0.7 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 9.77 µg/m³
  • PM10: 10.38 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.7 ppb
  • SO2: 0.7 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 10.26 µg/m³
  • PM10: 10.92 µg/m³
  • O3: 0.048 ppm
  • NO2: 0.7 ppb
  • SO2: 0.8 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

10 PM
44 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 10.57 µg/m³
  • PM10: 11.27 µg/m³
  • O3: 0.047 ppm
  • NO2: 0.8 ppb
  • SO2: 0.8 ppb
  • CO: 0.12 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: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 10.56 µg/m³
  • PM10: 11.28 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.8 ppb
  • SO2: 0.8 ppb
  • CO: 0.12 ppm

Health Recommendations:

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