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Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Fair

91°F

33°C

Humidity 63%
Wind Speed S 7 mph
Barometer 30.08 in
Dewpoint 77°F (25°C)
Visibility 10.00 mi
Heat Index104°F (40°C)
Last update 15 Aug 2:45 pm CDT
Extended Forecast for

Carterville IL

Extreme Heat Warning August 15, 03:09pm until August 16, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 15, 03:09pm until August 16, 08:00pm

    NOW until 8:00pm Sun

    Extreme Heat Warning

  • This Afternoon

    High: 98 °F

    Hot

  • Tonight

    Tonight: Mostly clear, with a low around 76. Calm wind becoming south southwest around 5 mph after midnight.

    Low: 76 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny and hot, with a high near 99. Heat index values as high as 107. West southwest wind 5 to 7 mph.

    High: 99 °F

    Hot

  • Sunday Night

    Sunday Night: A 30 percent chance of showers and thunderstorms, mainly between 2am and 5am. Partly cloudy, with a low around 72. Light north wind.

    Low: 72 °F

    Chance
    T-storms then
    Chance
    Showers

  • Monday

    Monday: A 30 percent chance of showers, mainly between 7am and 1pm. Partly sunny, with a high near 88. North northwest wind 5 to 8 mph.

    High: 88 °F

    Chance
    Showers

  • Monday Night

    Monday Night: Partly cloudy, with a low around 67. North wind around 5 mph becoming calm in the evening.

    Low: 67 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 91. Calm wind.

    High: 91 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 70. Light southeast wind.

    Low: 70 °F

    Mostly Clear

Detailed Forecast

This Afternoon
Sunny and hot, with a high near 98. Heat index values as high as 109. Southwest wind around 7 mph.
Tonight
Mostly clear, with a low around 76. Calm wind becoming south southwest around 5 mph after midnight.
Sunday
Mostly sunny and hot, with a high near 99. Heat index values as high as 107. West southwest wind 5 to 7 mph.
Sunday Night
A 30 percent chance of showers and thunderstorms, mainly between 2am and 5am. Partly cloudy, with a low around 72. Light north wind.
Monday
A 30 percent chance of showers, mainly between 7am and 1pm. Partly sunny, with a high near 88. North northwest wind 5 to 8 mph.
Monday Night
Partly cloudy, with a low around 67. North wind around 5 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 91. Calm wind.
Tuesday Night
Mostly clear, with a low around 70. Light southeast wind.
Wednesday
A chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 93. South wind 5 to 9 mph becoming west in the afternoon.
Wednesday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 68. North wind 5 to 7 mph.
Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 85. North wind 5 to 8 mph.
Thursday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 65. North northeast wind around 6 mph becoming calm in the evening.
Friday
A slight chance of showers. Mostly sunny, with a high near 86. Calm wind becoming north 5 to 7 mph in the morning.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Carterville IL
 37.76°N 89.09°W
Last Update:
1:26 pm CDT Aug 15, 2026
Forecast Valid:
3pm CDT Aug 15, 2026-6pm CDT Aug 21, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation