Current conditions at
St. Louis Downtown Airport (KCPS)
Lat: 38.56°NLon: 90.15°WElev: 410ft.
Fair
20°F
-7°C
| Humidity | 48% |
| Wind Speed | NW 9 mph |
| Barometer | 30.31 in (1027.0 mb) |
| Dewpoint | 3°F (-16°C) |
| Visibility | 10.00 mi |
| Wind Chill | 10°F (-12°C) |
| Last update | 17 Mar 9:53 am CDT |
Extended Forecast for
O'Fallon IL
Today
High: 34 °F
Increasing
CloudsTonight
Low: 31 °F
Chance Snow
then Chance
Rain/SnowWednesday
High: 63 °F
Becoming
SunnyWednesday Night
Low: 42 °F
Mostly Cloudy
Thursday
High: 72 °F
Mostly Sunny
Thursday Night
Low: 47 °F
Mostly Clear
Friday
High: 75 °F
Sunny
Friday Night
Low: 50 °F
Partly Cloudy
Saturday
High: 76 °F
Sunny
Detailed Forecast
Today
Increasing clouds, with a high near 34. Northwest wind 6 to 8 mph becoming southwest in the afternoon.
Tonight
A chance of snow before 4am, then a chance of rain. Cloudy, with a low around 31. Southeast wind 5 to 14 mph, with gusts as high as 23 mph. Chance of precipitation is 40%.
Wednesday
Mostly cloudy through mid morning, then gradual clearing, with a high near 63. South wind 9 to 14 mph becoming west in the afternoon. Winds could gust as high as 22 mph.
Wednesday Night
Mostly cloudy, with a low around 42. Light and variable wind.
Thursday
Mostly sunny, with a high near 72. South wind 5 to 7 mph.
Thursday Night
Mostly clear, with a low around 47.
Friday
Sunny, with a high near 75.
Friday Night
Partly cloudy, with a low around 50.
Saturday
Sunny, with a high near 76.
Saturday Night
Mostly clear, with a low around 53.
Sunday
Mostly sunny, with a high near 75.
Sunday Night
Partly cloudy, with a low around 41.
Monday
Partly sunny, with a high near 56.
Additional Forecasts and Information
Basemap Options
Click map to change the forecast location
Loading map...
Forecast AreaABOUT THIS FORECAST
Point Forecast:
O'Fallon IL
38.59°N 89.92°W (Elev. 551 ft)
38.59°N 89.92°W (Elev. 551 ft)
6:56 am CDT Mar 17, 2026
10am CDT Mar 17, 2026-6pm CDT Mar 23, 2026
Additional Resources
Radar & Satellite Image
Hourly Weather Forecast
