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.

Light Snow

10°F

-12°C

Humidity 92%
Wind Speed NE 10 mph
Barometer 30.31 in
Dewpoint 9°F (-13°C)
Visibility 1.00 mi
Wind Chill-4°F (-20°C)
Last update 24 Jan 6:45 pm CST
Extended Forecast for

Simpson IL

Cold Weather Advisory January 24, 06:54pm until January 26, 12:00am
Extreme Cold Warning January 26, 12:00am until January 27, 10:00am
Winter Storm Warning January 24, 06:54pm until January 25, 06:00pm
Click here for hazard details and duration
Cold Weather Advisory
Extreme Cold Warning
Winter Storm Warning
  •  
    Cold Weather Advisory January 24, 06:54pm until January 26, 12:00am
    Winter Storm Warning January 24, 06:54pm until January 25, 06:00pm

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Tonight

    Low: 13 °F

    Snow then
    Snow/Sleet

  • Sunday

    Sunday: Snow, mainly before 2pm. High near 19. North wind 8 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.

    High: 19 °F

    Snow then
    Snow Likely

  • Sunday Night

    Sunday Night: A 20 percent chance of snow before 7pm. Cloudy during the early evening, then gradual clearing, with a low around -1. Wind chill values as low as -12. North northwest wind 6 to 10 mph, with gusts as high as 23 mph.

    Low: -1 °F

    Slight Chance
    Snow then
    Partly Cloudy

  • Monday

    Monday: Sunny, with a high near 16. Wind chill values as low as -13. Northwest wind 5 to 7 mph becoming light and variable in the afternoon.

    High: 16 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around -1. Calm wind becoming southwest 5 to 7 mph after midnight. Winds could gust as high as 18 mph.

    Low: -1 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 28. Southwest wind 3 to 8 mph. Winds could gust as high as 18 mph.

    High: 28 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 5. Calm wind.

    Low: 5 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 26. Calm wind becoming west around 5 mph.

    High: 26 °F

    Partly Sunny

Detailed Forecast

Tonight
Snow before 1am, then snow, possibly mixed with sleet between 1am and 5am, then snow after 5am. Low around 13. North northeast wind 6 to 8 mph. Chance of precipitation is 100%. Total nighttime snow and sleet accumulation of 3 to 5 inches possible.
Sunday
Snow, mainly before 2pm. High near 19. North wind 8 to 13 mph, with gusts as high as 24 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 5 inches possible.
Sunday Night
A 20 percent chance of snow before 7pm. Cloudy during the early evening, then gradual clearing, with a low around -1. Wind chill values as low as -12. North northwest wind 6 to 10 mph, with gusts as high as 23 mph.
Monday
Sunny, with a high near 16. Wind chill values as low as -13. Northwest wind 5 to 7 mph becoming light and variable in the afternoon.
Monday Night
Mostly clear, with a low around -1. Calm wind becoming southwest 5 to 7 mph after midnight. Winds could gust as high as 18 mph.
Tuesday
Sunny, with a high near 28. Southwest wind 3 to 8 mph. Winds could gust as high as 18 mph.
Tuesday Night
Mostly cloudy, with a low around 5. Calm wind.
Wednesday
Partly sunny, with a high near 26. Calm wind becoming west around 5 mph.
Wednesday Night
Mostly cloudy, with a low around 2. Calm wind.
Thursday
Partly sunny, with a high near 20. Calm wind becoming north northwest around 6 mph.
Thursday Night
Partly cloudy, with a low around 0. Calm wind.
Friday
Mostly sunny, with a high near 21. Calm wind becoming north northwest around 5 mph.
Friday Night
Partly cloudy, with a low around 2. Calm wind.
Saturday
Mostly sunny, with a high near 24. Calm wind becoming north northwest around 5 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
Last Update:
6:27 pm CST Jan 24, 2026
Forecast Valid:
6pm CST Jan 24, 2026-6pm CST Jan 31, 2026
 
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Additional Resources

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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