Stay updated with real-time air quality in St. Charles, Missouri featuring accurate data on AQI, PM2.5, PM10, O3, NO2, SO2, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.
Live AQI (Air Quality Index)
51
Moderate
St. Charles, Missouri
Last updated: ... (Local time)
Good
Fine
Moderate
Poor
Very poor
Hazardous
3.98 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
20.25 μg/m³
0
55
155
255
425
605+
55.18 ppb
0
55
71
86
201
201+
0.45 ppb
0
36
76
186
605
1005+
3.38 ppb
0
54
101
361
1250
2050+
0.16 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
St. Charles, Missouri
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AQI 52
Moderate
9.99μg/m³
PM2.5
37.65μg/m³
PM10
34.92ppb
O3
0.62ppb
SO2
8.42ppb
NO2
0.25ppm
CO
AQI 52
Moderate
9.95μg/m³
PM2.5
37.93μg/m³
PM10
35.65ppb
O3
0.62ppb
SO2
7.70ppb
NO2
0.25ppm
CO
AQI 52
Moderate
9.93μg/m³
PM2.5
39.43μg/m³
PM10
35.24ppb
O3
0.62ppb
SO2
7.14ppb
NO2
0.25ppm
CO
AQI 52
Moderate
10.08μg/m³
PM2.5
40.37μg/m³
PM10
35.14ppb
O3
0.61ppb
SO2
7.44ppb
NO2
0.26ppm
CO
AQI 49
Good
8.83μg/m³
PM2.5
32.63μg/m³
PM10
35.06ppb
O3
0.69ppb
SO2
4.58ppb
NO2
0.24ppm
CO
AQI 52
Moderate
10.35μg/m³
PM2.5
40.12μg/m³
PM10
34.77ppb
O3
0.56ppb
SO2
5.62ppb
NO2
0.25ppm
CO
The air quality data for Missouri, USA is gathered from reliable sources such as satellites and monitoring stations, adhering to US EPA guidelines. With the help of advanced algorithms and machine learning, factors like traffic and population density are analyzed to deliver accurate and dependable results.
Source: Ambee Data Sources
Air quality updates for St. Charles, Missouri are available every hour.
St. Charles, Missouri experienced its worst air quality at 07:00:00, 2025-07-19.
The best air quality in St. Charles, Missouri was observed at 01:00:00 on 2025-07-19.
The air quality in St. Charles, Missouri right now is Moderate, with an AQI of 54.
In St. Charles, Missouri, PM2.5 is the most frequently found pollutant.
When air quality in St. Charles, Missouri is compromised, staying indoors and wearing a mask can reduce health risks.
St. Charles, Missouri currently has a PM2.5 concentration of 10.644 μg/m3.
St. Charles, Missouri currently has a PM10 concentration of 36.304 μg/m3.
The current carbon monoxide (CO) level in St. Charles, Missouri is 0.306 ppm.
The current sulfur dioxide (SO2) concentration in St. Charles, Missouri is 1.32 ppb.
St. Charles, Missouri currently has an ozone (O3) concentration of 31.272 ppm.
The current level of nitrogen dioxide (NO2) in St. Charles, Missouri is 7.172 ppb.
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