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

Hazardous Weather Conditions

Current conditions at

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Mostly Cloudy

79°F

26°C

Humidity 74%
Wind Speed Calm
Barometer 30.04 in
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 4 Aug 11:45 am CDT
Extended Forecast for

Herrin IL

  • This Afternoon

    This Afternoon: A 40 percent chance of showers and thunderstorms, mainly after 5pm. Partly sunny, with a high near 84. East northeast wind 3 to 6 mph.

    High: 84 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 10 percent chance of showers and thunderstorms before 7pm. Partly cloudy, with a low around 67. East northeast wind around 5 mph becoming calm in the evening.

    Low: 67 °F

    Slight Chance
    T-storms then
    Partly Cloudy

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 85. Light and variable wind.

    High: 85 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 68. Light east southeast wind.

    Low: 68 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 89. Light east southeast wind.

    High: 89 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 69. Calm wind.

    Low: 69 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 91. Light southeast wind.

    High: 91 °F

    Sunny

  • Thursday Night

    Thursday Night: Clear, with a low around 71. Light southeast wind.

    Low: 71 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 92. Calm wind becoming south southeast around 6 mph in the morning.

    High: 92 °F

    Sunny

Detailed Forecast

This Afternoon
A 40 percent chance of showers and thunderstorms, mainly after 5pm. Partly sunny, with a high near 84. East northeast wind 3 to 6 mph.
Tonight
A 10 percent chance of showers and thunderstorms before 7pm. Partly cloudy, with a low around 67. East northeast wind around 5 mph becoming calm in the evening.
Tuesday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 85. Light and variable wind.
Tuesday Night
Mostly clear, with a low around 68. Light east southeast wind.
Wednesday
Sunny, with a high near 89. Light east southeast wind.
Wednesday Night
Mostly clear, with a low around 69. Calm wind.
Thursday
Sunny, with a high near 91. Light southeast wind.
Thursday Night
Clear, with a low around 71. Light southeast wind.
Friday
Sunny, with a high near 92. Calm wind becoming south southeast around 6 mph in the morning.
Friday Night
Mostly clear, with a low around 72. Southeast wind 3 to 5 mph.
Saturday
Sunny, with a high near 92. South wind 3 to 7 mph.
Saturday Night
Mostly clear, with a low around 73. South southeast wind 3 to 6 mph.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 93. South southwest wind 3 to 7 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Herrin IL
 37.8°N 89.03°W
Last Update:
11:17 am CDT Aug 4, 2025
Forecast Valid:
12pm CDT Aug 4, 2025-6pm CDT Aug 10, 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