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Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Partly Cloudy

93°F

34°C

Humidity 53%
Wind Speed N 7 mph
Barometer 30.09 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index103°F (39°C)
Last update 17 Aug 11:45 am CDT
Extended Forecast for

4 Miles W Vienna IL

Heat Advisory August 17, 12:24pm until August 19, 07:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 17, 12:24pm until August 19, 07:00pm

    NOW until 7:00pm Tue

    Heat Advisory

  • This Afternoon

    High: 98 °F

    Slight Chance
    T-storms

  • Tonight

    Tonight: A 20 percent chance of showers and thunderstorms before 10pm. Partly cloudy, with a low around 75. Calm wind.

    Low: 75 °F

    Slight Chance
    T-storms then
    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 99. Heat index values as high as 110. Calm wind.

    High: 99 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 75. Calm wind.

    Low: 75 °F

    Mostly Clear

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms after 1pm. Sunny and hot, with a high near 97. Calm wind.

    High: 97 °F

    Sunny then
    Slight Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers and thunderstorms, mainly before 1am. Partly cloudy, with a low around 72. Calm wind.

    Low: 72 °F

    Chance
    T-storms then
    Chance
    Showers

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 91. Calm wind becoming north around 6 mph in the afternoon.

    High: 91 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 69. North northeast wind around 6 mph becoming calm in the evening.

    Low: 69 °F

    Partly Cloudy

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 98. Heat index values as high as 105. Light east wind.
Tonight
A 20 percent chance of showers and thunderstorms before 10pm. Partly cloudy, with a low around 75. Calm wind.
Monday
Sunny and hot, with a high near 99. Heat index values as high as 110. Calm wind.
Monday Night
Mostly clear, with a low around 75. Calm wind.
Tuesday
A 20 percent chance of showers and thunderstorms after 1pm. Sunny and hot, with a high near 97. Calm wind.
Tuesday Night
A 30 percent chance of showers and thunderstorms, mainly before 1am. Partly cloudy, with a low around 72. Calm wind.
Wednesday
A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 91. Calm wind becoming north around 6 mph in the afternoon.
Wednesday Night
Partly cloudy, with a low around 69. North northeast wind around 6 mph becoming calm in the evening.
Thursday
Mostly sunny, with a high near 89. North wind 3 to 6 mph.
Thursday Night
Partly cloudy, with a low around 68. North northeast wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 91. Calm wind becoming north northeast around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 69. Calm wind.
Saturday
Sunny, with a high near 92. Light north wind.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles W Vienna IL
 37.4°N 88.97°W
Last Update:
10:30 am CDT Aug 17, 2025
Forecast Valid:
12pm CDT Aug 17, 2025-6pm CDT Aug 23, 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