Weather in O'Fallon, Missouri
Thursday 19 November 2026
16°
Overcast
Feels like 12°
- High
- 18°
- Low
- 7°
- Humidity
- 57%
- Wind
- 18 km/h
Temperature and rain / O'Fallon
The coming days
High
22°
Low
-2°
Average high
13.7°
Average low
4.5°
Total rain
54.6 mm
Average rain
3.6 mm
Air quality - O'Fallon
Particles and ozone
Good
8.80 µg/m³
0-1212-3535-5555+
The air is clean: enjoy the outdoors.
PM108.90µg/m³
Ozone47µg/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 19°\n- Low of 8°
Need more information?
Our data is updated regularly to give you the most reliable forecast.
Last updated: 2026-11-11