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

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

82°F

28°C

Humidity 23%
Wind Speed SE 8 mph
Barometer 30.01 in
Dewpoint 41°F (5°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 9 Oct 5:50 pm CDT
Extended Forecast for

Glen Carbon IL

  • Tonight

    Tonight: Increasing clouds, with a low around 57. Southeast wind 5 to 9 mph.

    Low: 57 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Mostly cloudy, with a high near 81. Southeast wind 5 to 8 mph.

    High: 81 °F

    Mostly Cloudy

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 60. East wind 5 to 8 mph becoming light and variable after midnight.

    Low: 60 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly cloudy, then gradually becoming sunny, with a high near 84. Light and variable wind becoming northwest around 6 mph in the afternoon.

    High: 84 °F

    Decreasing
    Clouds

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 63. Calm wind becoming south around 5 mph after midnight.

    Low: 63 °F

    Mostly Clear

  • Columbus Day

    Columbus Day: Sunny, with a high near 93.

    High: 93 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 70.

    Low: 70 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 90.

    High: 90 °F

    Sunny

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 64.

    Low: 64 °F

    Mostly Clear
    then Chance
    Showers

Detailed Forecast

Tonight
Increasing clouds, with a low around 57. Southeast wind 5 to 9 mph.
Saturday
Mostly cloudy, with a high near 81. Southeast wind 5 to 8 mph.
Saturday Night
Mostly cloudy, with a low around 60. East wind 5 to 8 mph becoming light and variable after midnight.
Sunday
Mostly cloudy, then gradually becoming sunny, with a high near 84. Light and variable wind becoming northwest around 6 mph in the afternoon.
Sunday Night
Mostly clear, with a low around 63. Calm wind becoming south around 5 mph after midnight.
Columbus Day
Sunny, with a high near 93.
Monday Night
Mostly clear, with a low around 70.
Tuesday
Sunny, with a high near 90.
Tuesday Night
A 30 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 64.
Wednesday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 81. Chance of precipitation is 50%.
Wednesday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 62.
Thursday
A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 79.
Thursday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 57.
Friday
A 20 percent chance of showers. Partly sunny, with a high near 71.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Glen Carbon IL
 38.77°N 89.97°W (Elev. 548 ft)
Last Update:
5:41 pm CDT Oct 9, 2026
Forecast Valid:
5pm CDT Oct 9, 2026-6pm CDT Oct 16, 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