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

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

22°F

-6°C

Humidity 85%
Wind Speed S 6 mph
Barometer 30.39 in (1029.5 mb)
Dewpoint 18°F (-8°C)
Visibility 10.00 mi
Wind Chill14°F (-10°C)
Last update 12 Jan 1:53 am CST
Extended Forecast for

3 Miles SE Mascoutah IL

  • Overnight

    Overnight: Clear, with a low around 23. South wind 3 to 6 mph.

    Low: 23 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 54. Southwest wind 7 to 10 mph.

    High: 54 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 34. Southwest wind 6 to 8 mph.

    Low: 34 °F

    Mostly Clear

  • Tuesday

    Tuesday: Increasing clouds, with a high near 62. West wind 8 to 15 mph, with gusts as high as 25 mph.

    High: 62 °F

    Increasing
    Clouds

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers before midnight. Mostly cloudy, with a low around 39. West wind 7 to 9 mph.

    Low: 39 °F

    Chance
    Showers then
    Mostly Cloudy

  • Wednesday

    Wednesday: A 20 percent chance of showers after noon. Mostly cloudy, with a temperature falling to around 34 by 5pm. Breezy.

    High: 43 °F⇓

    Partly Sunny
    then Slight
    Chance
    Showers and
    Breezy

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 18.

    Low: 18 °F

    Mostly Cloudy

  • Thursday

    Thursday: Sunny, with a high near 31.

    High: 31 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 26.

    Low: 26 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Clear, with a low around 23. South wind 3 to 6 mph.
Monday
Sunny, with a high near 54. Southwest wind 7 to 10 mph.
Monday Night
Mostly clear, with a low around 34. Southwest wind 6 to 8 mph.
Tuesday
Increasing clouds, with a high near 62. West wind 8 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 30 percent chance of showers before midnight. Mostly cloudy, with a low around 39. West wind 7 to 9 mph.
Wednesday
A 20 percent chance of showers after noon. Mostly cloudy, with a temperature falling to around 34 by 5pm. Breezy.
Wednesday Night
Mostly cloudy, with a low around 18.
Thursday
Sunny, with a high near 31.
Thursday Night
Mostly cloudy, with a low around 26.
Friday
A 20 percent chance of snow showers after noon. Partly sunny, with a high near 42.
Friday Night
Mostly cloudy, with a low around 21.
Saturday
Partly sunny, with a high near 30.
Saturday Night
Partly cloudy, with a low around 12.
Sunday
Mostly sunny, with a high near 29.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles SE Mascoutah IL
 38.49°N 89.76°W (Elev. 427 ft)
Last Update:
2:41 am CST Jan 12, 2026
Forecast Valid:
2am CST Jan 12, 2026-6pm CST Jan 18, 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