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Today Hourly 7 days 30 days Air Quality
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Hourly Weather | Today › Wednesday, August 5, 2026
Active Weather Warnings
St. Louis, Missouri
3 AM
Night
68°
Feels Like 68°
0
Humidity: 81%
UV Index: 0
Wind: 4 mph
4 AM
Night
68°
Feels Like 66°
0
Humidity: 84%
UV Index: 0
Wind: 2 mph
5 AM
Cloudy Night
66°
Feels Like 66°
0
Humidity: 85%
UV Index: 0
Wind: 2 mph
6 AM
Cloudy Night
70°
Feels Like 70°
0
Humidity: 85%
UV Index: 0
Wind: 2 mph
7 AM
Cloudy Weather
72°
Feels Like 73°
0
Humidity: 79%
UV Index: 1
Wind: 2 mph
8 AM
Cloudy Weather
73°
Feels Like 79°
0
Humidity: 76%
UV Index: 2
Wind: 4 mph
9 AM
Cloudy Weather
77°
Feels Like 82°
0
Humidity: 67%
UV Index: 3
Wind: 5 mph
10 AM
Cloudy Weather
81°
Feels Like 88°
0
Humidity: 64%
UV Index: 4
Wind: 6 mph
11 AM
Cloudy Weather
82°
Feels Like 93°
0
Humidity: 61%
UV Index: 6
Wind: 6 mph
12 PM
Cloudy Weather
86°
Feels Like 97°
0
Humidity: 53%
UV Index: 8
Wind: 7 mph
1 PM
Cloudy Weather
88°
Feels Like 99°
3
Humidity: 49%
UV Index: 9
Wind: 7 mph
2 PM
Cloudy Weather
90°
Feels Like 99°
19
Humidity: 47%
UV Index: 8
Wind: 7 mph
3 PM
Cloudy Weather
91°
Feels Like 100°
19
Humidity: 47%
UV Index: 6
Wind: 6 mph
4 PM
Cloudy Weather
90°
Feels Like 99°
24
Humidity: 47%
UV Index: 4
Wind: 5 mph
5 PM
Cloudy Weather
90°
Feels Like 97°
47
Humidity: 49%
UV Index: 3
Wind: 1 mph
6 PM
Sunny with a Chance of Thunderstorms
82°
Feels Like 88°
51
Humidity: 74%
UV Index: 1
Wind: 2 mph
7 PM
Cloudy Weather
82°
Feels Like 88°
47
Humidity: 69%
UV Index: 1
Wind: 6 mph
8 PM
Cloudy Weather
81°
Feels Like 82°
49
Humidity: 68%
UV Index: 0
Wind: 6 mph
9 PM
Cloudy Night
81°
Feels Like 82°
49
Humidity: 68%
UV Index: 0
Wind: 5 mph
10 PM
Stormy Weather
73°
Feels Like 73°
58
Humidity: 90%
UV Index: 0
Wind: 5 mph
11 PM
Cloudy Night
73°
Feels Like 77°
49
Humidity: 86%
UV Index: 0
Wind: 5 mph

Hourly Air Quality Forecast - AQI (US EPA)

3 AM
36 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 8.65 µg/m³
  • PM10: 9 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.5 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

4 AM
37 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 8.86 µg/m³
  • PM10: 9.19 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.5 ppb
  • SO2: 0.5 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

5 AM
37 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 8.97 µg/m³
  • PM10: 9.29 µg/m³
  • O3: 0.033 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.

6 AM
38 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.04 µg/m³
  • PM10: 9.35 µg/m³
  • O3: 0.032 ppm
  • NO2: 0.4 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

7 AM
38 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.11 µg/m³
  • PM10: 9.41 µg/m³
  • O3: 0.030 ppm
  • NO2: 0.5 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

8 AM
38 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.12 µg/m³
  • PM10: 9.43 µg/m³
  • O3: 0.029 ppm
  • NO2: 0.7 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

9 AM
38 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.1 µg/m³
  • PM10: 9.42 µg/m³
  • O3: 0.029 ppm
  • NO2: 0.8 ppb
  • SO2: 0.4 ppb
  • CO: 0.11 ppm

Health Recommendations:

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

10 AM
38 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.11 µg/m³
  • PM10: 9.44 µg/m³
  • O3: 0.034 ppm
  • NO2: 0.7 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
46 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.16 µg/m³
  • PM10: 8.43 µg/m³
  • O3: 0.049 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
46 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 7.69 µg/m³
  • PM10: 7.94 µg/m³
  • O3: 0.049 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
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 7.7 µg/m³
  • PM10: 7.96 µg/m³
  • O3: 0.048 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
45 AQI
Good air quality Dominant pollutant: O3
Details

Pollutant Concentrations:

  • PM2.5: 8.29 µg/m³
  • PM10: 8.56 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.

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

Pollutant Concentrations:

  • PM2.5: 8.66 µg/m³
  • PM10: 8.95 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.

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

Pollutant Concentrations:

  • PM2.5: 8.84 µg/m³
  • PM10: 9.13 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.

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

Pollutant Concentrations:

  • PM2.5: 9.07 µg/m³
  • PM10: 9.36 µg/m³
  • O3: 0.039 ppm
  • NO2: 0.6 ppb
  • SO2: 0.2 ppb
  • CO: 0.12 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: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.35 µg/m³
  • PM10: 9.64 µg/m³
  • O3: 0.029 ppm
  • NO2: 1.3 ppb
  • SO2: 0.2 ppb
  • CO: 0.13 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: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.59 µg/m³
  • PM10: 9.89 µg/m³
  • O3: 0.022 ppm
  • NO2: 1.8 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

8 PM
40 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.69 µg/m³
  • PM10: 10 µg/m³
  • O3: 0.018 ppm
  • NO2: 1.9 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 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: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.81 µg/m³
  • PM10: 10.12 µg/m³
  • O3: 0.017 ppm
  • NO2: 1.7 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

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

Pollutant Concentrations:

  • PM2.5: 9.85 µg/m³
  • PM10: 10.16 µg/m³
  • O3: 0.018 ppm
  • NO2: 1.6 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

11 PM
41 AQI
Good air quality Dominant pollutant: PM2.5
Details

Pollutant Concentrations:

  • PM2.5: 9.74 µg/m³
  • PM10: 10.05 µg/m³
  • O3: 0.025 ppm
  • NO2: 1.2 ppb
  • SO2: 0.1 ppb
  • CO: 0.13 ppm

Health Recommendations:

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

Current Real-Time Air Quality Report

Weather Alerts and Warnings for St. Louis

Severe Future Possible

Flood Watch

Flood Watch issued August 5 at 1:57AM CDT until August 6 at 10:00AM CDT by NWS St Louis MO
Aug 5, 10:00 PM → Aug 6, 10:00 AM
WHAT: Flash flooding caused by excessive rainfall is possible.

WHERE: Portions of Illinois, including the following areas, Adams
IL, Brown IL, Calhoun IL and Pike IL and Missouri, including the
following areas, Audrain MO, Boone MO, Callaway MO, Cole MO,
Crawford MO, Franklin MO, Gasconade MO, Jefferson MO, Knox MO,
Lewis MO, Lincoln MO, Marion MO, Moniteau MO, Monroe MO, Montgomery
MO, Osage MO, Pike MO, Ralls MO, Saint Charles MO, Saint Louis City
MO, Saint Louis MO, Shelby MO, Warren MO and Washington MO.

WHEN: From this evening through Thursday morning.

IMPACTS: Excessive runoff may result in flooding of rivers,
creeks, streams, and other low-lying and flood-prone locations.

ADDITIONAL DETAILS:
- Training thunderstorms with high rainfall rates are expected
within the watch area late this evening into Thursday morning.
+ Read More
You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.
Updated: Aug 5, 2:29 AM Source: NWS Alert

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