Hourly Weather | Today Monday, January 19, 2026
St. Louis, Missouri
3 AM
Cloudy Night
18°
Feels Like
0
Humidity: 59%
Wind: 16 mph
UV Index: 0
4 AM
Cloudy Night
16°
Feels Like -2°
0
Humidity: 56%
Wind: 16 mph
UV Index: 0
5 AM
Cloudy Night
14°
Feels Like -6°
0
Humidity: 52%
Wind: 15 mph
UV Index: 0
6 AM
Cloudy Night
12°
Feels Like -8°
0
Humidity: 50%
Wind: 15 mph
UV Index: 0
7 AM
Cloudy Night
10°
Feels Like -9°
0
Humidity: 51%
Wind: 15 mph
UV Index: 0
8 AM
Cloudy Weather
Feels Like -9°
0
Humidity: 52%
Wind: 16 mph
UV Index: 1
9 AM
Cloudy Weather
12°
Feels Like -6°
0
Humidity: 47%
Wind: 16 mph
UV Index: 2
10 AM
Cloudy Weather
16°
Feels Like
0
Humidity: 40%
Wind: 15 mph
UV Index: 2
11 AM
Cloudy Weather
18°
Feels Like
0
Humidity: 35%
Wind: 15 mph
UV Index: 3
12 PM
Cloudy Weather
19°
Feels Like
0
Humidity: 33%
Wind: 14 mph
UV Index: 3
1 PM
Cloudy Weather
21°
Feels Like
0
Humidity: 30%
Wind: 16 mph
UV Index: 3
2 PM
Cloudy Weather
21°
Feels Like
0
Humidity: 28%
Wind: 15 mph
UV Index: 2
3 PM
Cloudy Weather
23°
Feels Like 10°
0
Humidity: 26%
Wind: 14 mph
UV Index: 2
4 PM
Cloudy Weather
21°
Feels Like
0
Humidity: 28%
Wind: 13 mph
UV Index: 1
5 PM
Cloudy Weather
21°
Feels Like
0
Humidity: 29%
Wind: 10 mph
UV Index: 0
6 PM
Cloudy Night
19°
Feels Like 10°
0
Humidity: 31%
Wind: 9 mph
UV Index: 0
7 PM
Night
19°
Feels Like 12°
0
Humidity: 35%
Wind: 7 mph
UV Index: 0
8 PM
Night
18°
Feels Like 10°
0
Humidity: 38%
Wind: 7 mph
UV Index: 0
9 PM
Night
18°
Feels Like 10°
0
Humidity: 41%
Wind: 7 mph
UV Index: 0
10 PM
Night
18°
Feels Like 10°
0
Humidity: 43%
Wind: 7 mph
UV Index: 0
11 PM
Night
18°
Feels Like 10°
0
Humidity: 44%
Wind: 7 mph
UV Index: 0

Hourly Air Quality Forecast - AQI (US EPA)

3 AM
39 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 1.46 µg/m³
  • O3: 0.042 ppm
  • NO2: 0.8 ppb
  • SO2: 0.4 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

4 AM
40 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.84 µg/m³
  • PM10: 0.98 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.7 ppb
  • SO2: 0.4 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

5 AM
41 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 0.67 µg/m³
  • PM10: 0.76 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.6 ppb
  • SO2: 0.4 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.56 µg/m³
  • PM10: 0.61 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.52 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.7 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.8 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.042 ppm
  • NO2: 0.7 ppb
  • SO2: 0.3 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.042 ppm
  • NO2: 0.6 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.043 ppm
  • NO2: 0.5 ppb
  • SO2: 0.3 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.5 µg/m³
  • O3: 0.044 ppm
  • NO2: 0.5 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.5 µg/m³
  • PM10: 0.52 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.4 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 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: 0.53 µg/m³
  • PM10: 0.58 µg/m³
  • O3: 0.046 ppm
  • NO2: 0.5 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 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: 0.63 µg/m³
  • PM10: 0.7 µg/m³
  • O3: 0.045 ppm
  • NO2: 0.7 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.77 µg/m³
  • PM10: 0.86 µg/m³
  • O3: 0.044 ppm
  • NO2: 1.2 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 0.91 µg/m³
  • PM10: 1.02 µg/m³
  • O3: 0.042 ppm
  • NO2: 1.7 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.05 µg/m³
  • PM10: 1.22 µg/m³
  • O3: 0.040 ppm
  • NO2: 2 ppb
  • SO2: 0.2 ppb
  • CO: 0.14 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.23 µg/m³
  • PM10: 1.44 µg/m³
  • O3: 0.039 ppm
  • NO2: 2.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.41 µg/m³
  • PM10: 1.65 µg/m³
  • O3: 0.038 ppm
  • NO2: 2.1 ppb
  • SO2: 0.1 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.55 µg/m³
  • PM10: 1.81 µg/m³
  • O3: 0.037 ppm
  • NO2: 2 ppb
  • SO2: 0.2 ppb
  • CO: 0.15 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 1.65 µg/m³
  • PM10: 1.91 µg/m³
  • O3: 0.036 ppm
  • NO2: 2 ppb
  • SO2: 0.2 ppb
  • CO: 0.15 ppm

Health Recommendations:

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