Air Quality in St. Louis, United States

Drizzle
19.8°C · 96.3% humidity
19.8°
Feels 19.8°
44
Good
Air quality is satisfactory. Enjoy outdoor activities.
5 stations

Nearby Monitoring Stations

AQI Forecast
34 9am
54
34
44 12pm
41
39
38 3pm
37
36
35 6pm
35
35
34 9pm
34
34
34 12am
27
27
27 3am
27
27
34 6am
34
25
AD 728×90

Air Quality Index Trend

45h · 6 stn

St. Louis's air quality is primarily affected by vehicle emissions and industrial activity. Seasonal wildfire smoke and weather patterns can cause periodic air quality deterioration.

96.3%
Humidity
44.1 km/h
Wind NE
1018.9 hPa
Pressure
19.9
UV Extreme
GoodModerateUSGUnhealthyVery UnhealthyHazardous

Which pollutant is driving the AQI?

PM2.5▲
44
10.49 µg/m³
PM10
13
13.7 µg/m³
050100150200300500

What is the weather forecast for St. Louis?

Temperature & Precipitation

PM2.5 Trend

45h · 6 stations
PM2.510.49 µg/m³ ✓ WHO
Good
PM1013.7 µg/m³
Good
UV INDEX19.9
Extreme
AD 300×250
Station readings (5 stations within 25 km)
10.49
Median
8.94
Average
5.0
Low
12.6
High
PM2.5 µg/m³ · Model: 8.2 · Bias: -2.3

What is the 7-day forecast for St. Louis?

09-05
26.6° 19.8°
3.37 mm
09-06
38.4° 18.6°
3.06 mm
09-07
29.2° 22.6°
09-08
25.2° 21.0°
9.88 mm
09-09
24.4° 16.2°
8.12 mm
09-10
32.1° 19.3°
0.38 mm
09-11
38.3° 20.3°
0.06 mm
Both models agree Avg diff: 6.4°C

Where are air quality stations near St. Louis?

48
Branch Street, Missouri, USA
3.3 km PM2.5: 11.5 µg/m³
49
East St. Louis, Illinois, USA
3.7 km PM2.5: 11.8 µg/m³
52
East St. Louis, Illinois, USA
3.7 km PM2.5: 12.6 µg/m³
28
Forest Park, Missouri, USA
7.2 km PM2.5: 6.7 µg/m³
21
Ladue, Missouri, USA
13.5 km PM2.5: 5.0 µg/m³
46
Arnold West, Missouri, USA
26.4 km PM2.5: 11.0 µg/m³
68
Arnold West, Missouri, USA
26.4 km PM2.5: 20.2 µg/m³
72
Arnold West, Missouri, USA
26.4 km PM2.5: 22.1 µg/m³
51
Arnold West, Missouri, USA
26.4 km PM2.5: 12.1 µg/m³
49
Arnold West, Missouri, USA
26.4 km PM2.5: 11.8 µg/m³

What cities are near St. Louis?

48 East Saint Louis 41 Granite City 27 University City 25 Clayton 39 Lemay 30 Webster Groves 36 Affton 32 Ferguson 27 Overland 41 Mehlville
Get AQI alerts for St. Louis

Notify me when air quality reaches:

Free · No account · Unsubscribe any time

Data sources: AQI from ground-level monitoring stations via AQICN. Weather forecast from ECMWF (IFS & CAMS models). AQI calculated using US EPA standard. Updated 2026-09-05T17:30 UTC.