Weather in O'Fallon, Missouri
Monday 9 November 2026
18°
Clear sky
Feels like 16°
- High
- 21°
- Low
- 3°
- Humidity
- 70%
- Wind
- 15 km/h
Temperature and rain / O'Fallon
The coming days
High
22°
Low
-2°
Average high
16.4°
Average low
5.7°
Total rain
30.9 mm
Average rain
2.1 mm
Air quality - O'Fallon
Particles and ozone
Good
8.70 µg/m³
0-1212-3535-5555+
The air is clean: enjoy the outdoors.
PM108.80µg/m³
Ozone33µg/m³
Data updated hourly
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Frequently asked questions
Quick answers about the weather in O'Fallon
Tomorrow in O'Fallon, expect Clear sky ☀️, with:\n\n- High of 17°\n- Low of 2°
Need more information?
Our data is updated regularly to give you the most reliable forecast.
Last updated: 2026-11-09