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

71°F

22°C

Humidity 90%
Wind Speed Calm
Barometer 30.01 in (1015.9 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Last update 14 Oct 7:53 pm CDT
Extended Forecast for

Mascoutah IL

  • Tonight

    Tonight: Isolated showers between 3am and 4am, then isolated showers and thunderstorms after 4am. Cloudy, with a low around 67. Calm wind. Chance of precipitation is 20%.

    Low: 67 °F

    Cloudy then
    Isolated
    T-storms

  • Thursday

    Thursday: Showers and thunderstorms, mainly before 1pm. High near 84. Light and variable wind becoming southwest 6 to 11 mph in the morning. Chance of precipitation is 80%.

    High: 84 °F

    Showers then
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 50. Southwest wind 7 to 17 mph becoming northwest after midnight. Winds could gust as high as 26 mph. Chance of precipitation is 50%.

    Low: 50 °F

    Chance
    T-storms then
    Chance
    Showers

  • Friday

    Friday: Mostly cloudy, with a high near 57. Breezy, with a northwest wind 18 to 23 mph, with gusts as high as 31 mph.

    High: 57 °F

    Mostly Cloudy
    and Breezy

  • Friday Night

    Friday Night: Partly cloudy, with a low around 40. North wind 9 to 15 mph, with gusts as high as 22 mph.

    Low: 40 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 62.

    High: 62 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 36.

    Low: 36 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 67.

    High: 67 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 40.

    Low: 40 °F

    Mostly Clear

Detailed Forecast

Tonight
Isolated showers between 3am and 4am, then isolated showers and thunderstorms after 4am. Cloudy, with a low around 67. Calm wind. Chance of precipitation is 20%.
Thursday
Showers and thunderstorms, mainly before 1pm. High near 84. Light and variable wind becoming southwest 6 to 11 mph in the morning. Chance of precipitation is 80%.
Thursday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 50. Southwest wind 7 to 17 mph becoming northwest after midnight. Winds could gust as high as 26 mph. Chance of precipitation is 50%.
Friday
Mostly cloudy, with a high near 57. Breezy, with a northwest wind 18 to 23 mph, with gusts as high as 31 mph.
Friday Night
Partly cloudy, with a low around 40. North wind 9 to 15 mph, with gusts as high as 22 mph.
Saturday
Sunny, with a high near 62.
Saturday Night
Clear, with a low around 36.
Sunday
Sunny, with a high near 67.
Sunday Night
Mostly clear, with a low around 40.
Monday
Mostly sunny, with a high near 73.
Monday Night
Partly cloudy, with a low around 44.
Tuesday
Mostly sunny, with a high near 75.
Tuesday Night
Mostly clear, with a low around 49.
Wednesday
Sunny, with a high near 80.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Mascoutah IL
 38.52°N 89.81°W (Elev. 423 ft)
Last Update:
8:25 pm CDT Oct 14, 2026
Forecast Valid:
8pm CDT Oct 14, 2026-6pm CDT Oct 21, 2026
 
Forecast Discussion
 
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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