National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Overcast

9°F

-13°C

Humidity 30%
Wind Speed N 16 G 25 mph
Barometer 30.71 in (1040.6 mb)
Dewpoint -16°F (-27°C)
Visibility 10.00 mi
Wind Chill-8°F (-22°C)
Last update 23 Jan 12:53 pm CST
Extended Forecast for

O'Fallon IL

Cold Weather Advisory January 24, 12:00am until January 24, 12:00pm
Winter Storm Warning January 24, 12:00am until January 25, 06:00pm
Click here for hazard details and duration
Cold Weather Advisory
Winter Storm Warning

  • This Afternoon

    This Afternoon: Mostly cloudy and cold, with a high near 14. North wind around 16 mph, with gusts as high as 24 mph.

    High: 14 °F

    Cold

  • Tonight

    Tonight: Cloudy, with a low around 4. Wind chill values as low as -10. Northeast wind 11 to 13 mph, with gusts as high as 21 mph.

    Low: 4 °F

    Cloudy

  • Saturday

    Saturday: Snow, mainly after noon. High near 12. Wind chill values as low as -10. Northeast wind 10 to 13 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New snow accumulation of 1 to 3 inches possible.

    High: 12 °F

    Chance Snow
    then Snow

  • Saturday Night

    Saturday Night: Snow, mainly after 9pm. The snow could be heavy at times. Low around 10. Northeast wind 9 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.

    Low: 10 °F

    Heavy Snow

  • Sunday

    Sunday: Snow, mainly before noon. High near 15. North wind 11 to 14 mph, with gusts as high as 21 mph. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.

    High: 15 °F

    Snow then
    Chance Snow

  • Sunday Night

    Sunday Night: A 20 percent chance of snow before midnight. Mostly cloudy, with a low around -1.

    Low: -1 °F

    Slight Chance
    Snow then
    Partly Cloudy

  • Monday

    Monday: Mostly sunny and cold, with a high near 16.

    High: 16 °F

    Cold

  • Monday Night

    Monday Night: Clear, with a low around 5.

    Low: 5 °F

    Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 32.

    High: 32 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Mostly cloudy and cold, with a high near 14. North wind around 16 mph, with gusts as high as 24 mph.
Tonight
Cloudy, with a low around 4. Wind chill values as low as -10. Northeast wind 11 to 13 mph, with gusts as high as 21 mph.
Saturday
Snow, mainly after noon. High near 12. Wind chill values as low as -10. Northeast wind 10 to 13 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New snow accumulation of 1 to 3 inches possible.
Saturday Night
Snow, mainly after 9pm. The snow could be heavy at times. Low around 10. Northeast wind 9 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.
Sunday
Snow, mainly before noon. High near 15. North wind 11 to 14 mph, with gusts as high as 21 mph. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
Sunday Night
A 20 percent chance of snow before midnight. Mostly cloudy, with a low around -1.
Monday
Mostly sunny and cold, with a high near 16.
Monday Night
Clear, with a low around 5.
Tuesday
Mostly sunny, with a high near 32.
Tuesday Night
Mostly cloudy, with a low around 9.
Wednesday
Partly sunny, with a high near 23.
Wednesday Night
Partly cloudy, with a low around 3.
Thursday
Mostly sunny and cold, with a high near 18.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
O'Fallon IL
 38.59°N 89.95°W (Elev. 545 ft)
Last Update:
11:11 am CST Jan 23, 2026
Forecast Valid:
1pm CST Jan 23, 2026-6pm CST Jan 29, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation