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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

74°F

23°C

Humidity 95%
Wind Speed Calm
Barometer 30.02 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Last update 18 Aug 2:55 am CDT
Extended Forecast for

Marion IL

Heat Advisory August 18, 03:03am until August 19, 07:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 18, 03:03am until August 19, 07:00pm

    NOW until 7:00pm Tue

    Heat Advisory

  • Overnight

    Low: 75 °F

    Partly Cloudy

  • Monday

    Monday: Sunny and hot, with a high near 99. Heat index values as high as 105. East southeast wind 3 to 6 mph.

    High: 99 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 74. East wind around 5 mph becoming calm in the evening.

    Low: 74 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 97. Calm wind becoming west northwest around 5 mph in the afternoon.

    High: 97 °F

    Sunny then
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 73. Calm wind.

    Low: 73 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 92. Calm wind becoming north northeast 5 to 9 mph in the morning.

    High: 92 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 68. North northeast wind 5 to 8 mph.

    Low: 68 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 89. North northeast wind 6 to 9 mph.

    High: 89 °F

    Mostly Sunny

Detailed Forecast

Overnight
Partly cloudy, with a low around 75. Calm wind.
Monday
Sunny and hot, with a high near 99. Heat index values as high as 105. East southeast wind 3 to 6 mph.
Monday Night
Mostly clear, with a low around 74. East wind around 5 mph becoming calm in the evening.
Tuesday
A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 97. Calm wind becoming west northwest around 5 mph in the afternoon.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 73. Calm wind.
Wednesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 92. Calm wind becoming north northeast 5 to 9 mph in the morning.
Wednesday Night
Partly cloudy, with a low around 68. North northeast wind 5 to 8 mph.
Thursday
Mostly sunny, with a high near 89. North northeast wind 6 to 9 mph.
Thursday Night
Mostly clear, with a low around 67. North northeast wind 5 to 7 mph becoming calm in the evening.
Friday
Sunny, with a high near 91. North northeast wind 3 to 6 mph.
Friday Night
Mostly clear, with a low around 67. North wind around 5 mph becoming calm in the evening.
Saturday
Sunny, with a high near 91. Calm wind becoming north northwest around 6 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 65. North wind around 6 mph becoming calm in the evening.
Sunday
Sunny, with a high near 86. North wind 3 to 8 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Marion IL
 37.76°N 88.95°W
Last Update:
2:30 am CDT Aug 18, 2025
Forecast Valid:
3am CDT Aug 18, 2025-6pm CDT Aug 24, 2025
 
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