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.

Thunderstorm in Vicinity

73°F

23°C

Humidity 76%
Wind Speed Calm
Barometer 29.94 in
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Last update 14 Oct 3:55 am CDT
Extended Forecast for

Glen Carbon IL

  • Overnight

    Overnight: Showers and thunderstorms likely, mainly after 5am. Mostly cloudy, with a low around 72. West wind around 6 mph. Chance of precipitation is 60%.

    Low: 72 °F

    T-storms
    Likely

  • Wednesday

    Wednesday: Showers and thunderstorms before 11am, then showers likely and possibly a thunderstorm between 11am and 1pm, then a chance of showers and thunderstorms after 1pm. High near 79. West wind 5 to 7 mph becoming north in the morning. Chance of precipitation is 90%.

    High: 79 °F

    T-storms then
    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 66. North wind 5 to 7 mph becoming east after midnight. Chance of precipitation is 30%.

    Low: 66 °F

    Chance
    T-storms

  • Thursday

    Thursday: Showers and possibly a thunderstorm before noon, then a chance of showers and thunderstorms between noon and 2pm, then showers likely and possibly a thunderstorm after 2pm. High near 83. East wind 7 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 80%.

    High: 83 °F

    Showers

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm before 1am, then a chance of showers. Mostly cloudy, with a low around 50. Breezy, with a southwest wind 8 to 13 mph becoming northwest 15 to 20 mph after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 70%.

    Low: 50 °F

    Showers
    Likely and
    Breezy

  • Friday

    Friday: Mostly sunny, with a high near 61. Breezy.

    High: 61 °F

    Mostly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 62.

    High: 62 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 38.

    Low: 38 °F

    Clear

Detailed Forecast

Overnight
Showers and thunderstorms likely, mainly after 5am. Mostly cloudy, with a low around 72. West wind around 6 mph. Chance of precipitation is 60%.
Wednesday
Showers and thunderstorms before 11am, then showers likely and possibly a thunderstorm between 11am and 1pm, then a chance of showers and thunderstorms after 1pm. High near 79. West wind 5 to 7 mph becoming north in the morning. Chance of precipitation is 90%.
Wednesday Night
A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 66. North wind 5 to 7 mph becoming east after midnight. Chance of precipitation is 30%.
Thursday
Showers and possibly a thunderstorm before noon, then a chance of showers and thunderstorms between noon and 2pm, then showers likely and possibly a thunderstorm after 2pm. High near 83. East wind 7 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 80%.
Thursday Night
Showers likely and possibly a thunderstorm before 1am, then a chance of showers. Mostly cloudy, with a low around 50. Breezy, with a southwest wind 8 to 13 mph becoming northwest 15 to 20 mph after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 70%.
Friday
Mostly sunny, with a high near 61. Breezy.
Friday Night
Mostly clear, with a low around 39.
Saturday
Sunny, with a high near 62.
Saturday Night
Clear, with a low around 38.
Sunday
Sunny, with a high near 69.
Sunday Night
Partly cloudy, with a low around 45.
Monday
Partly sunny, with a high near 73.
Monday Night
Partly cloudy, with a low around 48.
Tuesday
Mostly sunny, with a high near 78.
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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:
1:26 am CDT Oct 14, 2026
Forecast Valid:
4am CDT Oct 14, 2026-6pm CDT Oct 20, 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