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

Dangerous Heat over the South-Central and Southwest U.S. Through Next Week

Dangerous heat persists across the Desert Southwest through this weekend and across the Southern Plains and Lower Mississippi Valley through at least the middle of next week. Numerous daily record high temperatures are expected through at least Tuesday for much of Texas and Oklahoma as well as portions of Louisiana, New Mexico, and Arizona. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

79°F

26°C

Humidity 48%
Wind Speed NW 7 mph
Barometer 30.11 in
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 23 Aug 11:50 am CDT
Extended Forecast for

Glen Carbon IL

  • This Afternoon

    This Afternoon: Sunny, with a high near 82. Northwest wind around 8 mph.

    High: 82 °F

    Sunny

  • Tonight

    Tonight: Patchy fog after 5am. Otherwise, partly cloudy, with a low around 59. North wind around 5 mph becoming calm in the evening.

    Low: 59 °F

    Partly Cloudy
    then Patchy
    Fog

  • Monday

    Monday: Patchy fog before 9am. Otherwise, mostly sunny, with a high near 83. Light east wind.

    High: 83 °F

    Patchy Fog
    then Mostly
    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 62. Light east wind.

    Low: 62 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 84. Southeast wind 3 to 6 mph.

    High: 84 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 67.

    Low: 67 °F

    Partly Cloudy

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88.

    High: 88 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly clear, with a low around 68.

    Low: 68 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: Sunny, with a high near 87.

    High: 87 °F

    Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 82. Northwest wind around 8 mph.
Tonight
Patchy fog after 5am. Otherwise, partly cloudy, with a low around 59. North wind around 5 mph becoming calm in the evening.
Monday
Patchy fog before 9am. Otherwise, mostly sunny, with a high near 83. Light east wind.
Monday Night
Mostly clear, with a low around 62. Light east wind.
Tuesday
Mostly sunny, with a high near 84. Southeast wind 3 to 6 mph.
Tuesday Night
Partly cloudy, with a low around 67.
Wednesday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88.
Wednesday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly clear, with a low around 68.
Thursday
Sunny, with a high near 87.
Thursday Night
Mostly clear, with a low around 66.
Friday
Sunny, with a high near 85.
Friday Night
Mostly clear, with a low around 67.
Saturday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 86.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Glen Carbon IL
 38.79°N 89.97°W (Elev. 558 ft)
Last Update:
11:56 am CDT Aug 23, 2026
Forecast Valid:
12pm CDT Aug 23, 2026-6pm CDT Aug 29, 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