What is the air quality in O'Fallon today?

The current Air Quality Index (AQI) in O'Fallon is 42 (Good). PM2.5 concentration is 10.1 µg/m³.

What is the temperature in O'Fallon right now?

The current temperature in O'Fallon is 14.7°C (feels like 14.7°C). Humidity is 84.5% and wind speed is 40.8 km/h.

Is it safe to go outside in O'Fallon?

Air quality is satisfactory. Enjoy outdoor activities. The UV Index is 0.0 (Low).

Air Quality in O'Fallon, United States

Rain

14.7°C · 84.5% humidity

14.7°

Feels 14.7°

Good

Air quality is satisfactory. Enjoy outdoor activities.

1 station

Nearby Monitoring Stations

AQI Forecast

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Air Quality Index Trend

46h · 3 stn

View full history →

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

84.5%

Humidity

40.8 km/h

Wind E

1020.2 hPa

Pressure

0.0

UV Low

GoodModerateUSGUnhealthyVery UnhealthyHazardous

Which pollutant is driving the AQI?

PM2.5▲

10.1 µg/m³

PM10

27.4 µg/m³

050100150200300500

What is the weather forecast for O'Fallon?

Temperature & Precipitation

PM2.5 Trend

46h · 3 stations

PM2.510.1 µg/m³ ✓ WHO

Good

PM1027.4 µg/m³

Good

UV INDEX0.0

Low

Station readings (1 station within 25 km)

10.1

Median

10.1

Average

10.1

Low

10.1

High

PM2.5 µg/m³ · Model: 8.2 · Bias: -1.9

What is the 7-day forecast for O'Fallon?

10-20

13.5° 2.4°

0.06 mm

10-21

24.6° 12.5°

5.44 mm

10-22

21.8° 8.8°

2.19 mm

10-23

12.9° 7.4°

10.06 mm

10-24

25.3° 10.1°

10-25

17.2° 2.7°

10-26

25.6° 5.7°

0.06 mm

Both models agree Avg diff: 4.6°C

Where are air quality stations near O'Fallon?

East St. Louis, Illinois, USA

21.8 km PM2.5: 10.1 µg/m³

Branch Street, Missouri, USA

25.2 km PM2.5: 12.6 µg/m³

What cities are near O'Fallon?

38 Fairview Heights 38 Belleville 38 Collinsville 41 East Saint Louis 35 Granite City 30 Edwardsville 37 St. Louis 39 Lemay 35 Spanish Lake 36 University City

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Data sources: AQI from ground-level monitoring stations via AQICN. Weather forecast from ECMWF (IFS & CAMS models). AQI calculated using US EPA standard. Updated 2026-10-20T21:44 UTC.