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

48°F

9°C

Humidity 89%
Wind Speed Calm
Barometer 29.84 in (1010.4 mb)
Dewpoint 45°F (7°C)
Visibility 10.00 mi
Last update 5 Nov 2:53 am CST
Extended Forecast for

Mascoutah IL

  • Overnight

    Overnight: Patchy fog after 4am. Otherwise, mostly clear, with a low around 45. Southwest wind around 6 mph.

    Low: 45 °F

    Patchy Fog

  • Thursday

    Thursday: Increasing clouds, with a high near 64. West wind 5 to 13 mph, with gusts as high as 20 mph.

    High: 64 °F

    Increasing
    Clouds

  • Thursday Night

    Thursday Night: A slight chance of rain between 9pm and 10pm. Mostly cloudy, with a low around 45. Northwest wind around 8 mph. Chance of precipitation is 20%.

    Low: 45 °F

    Slight Chance
    Rain then
    Mostly Cloudy

  • Friday

    Friday: Mostly cloudy, then gradually becoming sunny, with a high near 55. North wind 7 to 11 mph.

    High: 55 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Mostly clear, with a low around 32. North wind around 6 mph becoming calm in the evening.

    Low: 32 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 54.

    High: 54 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 32.

    Low: 32 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 59.

    High: 59 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 36.

    Low: 36 °F

    Clear

Detailed Forecast

Overnight
Patchy fog after 4am. Otherwise, mostly clear, with a low around 45. Southwest wind around 6 mph.
Thursday
Increasing clouds, with a high near 64. West wind 5 to 13 mph, with gusts as high as 20 mph.
Thursday Night
A slight chance of rain between 9pm and 10pm. Mostly cloudy, with a low around 45. Northwest wind around 8 mph. Chance of precipitation is 20%.
Friday
Mostly cloudy, then gradually becoming sunny, with a high near 55. North wind 7 to 11 mph.
Friday Night
Mostly clear, with a low around 32. North wind around 6 mph becoming calm in the evening.
Saturday
Sunny, with a high near 54.
Saturday Night
Mostly clear, with a low around 32.
Sunday
Sunny, with a high near 59.
Sunday Night
Clear, with a low around 36.
Monday
Sunny, with a high near 66.
Monday Night
Clear, with a low around 40.
Tuesday
Sunny, with a high near 67.
Tuesday Night
Mostly clear, with a low around 41.
Veterans Day
Mostly sunny, with a high near 66.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Mascoutah IL
 38.5°N 89.78°W (Elev. 440 ft)
Last Update:
1:46 am CST Nov 5, 2026
Forecast Valid:
3am CST Nov 5, 2026-6pm CST Nov 11, 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