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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

75°F

24°C

Humidity 65%
Wind Speed SW 16 mph
Barometer 29.69 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 17 Jun 8:47 am CDT
Extended Forecast for

Simpson IL

Wind Advisory June 17, 01:00pm until June 17, 08:00pm
Click here for hazard details and duration
Wind Advisory

  • Today

    Today: Sunny, with a high near 89. Breezy, with a south southwest wind 5 to 10 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 37 mph.

    High: 89 °F

    Sunny then
    Sunny and
    Breezy

  • Tonight

    Tonight: Showers and thunderstorms likely before 4am, then a chance of showers. Increasing clouds, with a low around 74. Southwest wind 8 to 17 mph, with gusts as high as 33 mph. Chance of precipitation is 70%.

    Low: 74 °F

    Slight Chance
    T-storms then
    Showers
    Likely

  • Thursday

    Thursday: A 30 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 87. West southwest wind around 6 mph becoming north northwest in the afternoon.

    High: 87 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: A 30 percent chance of showers, mainly before 1am. Mostly cloudy, with a low around 64. Light north wind.

    Low: 64 °F

    Chance
    Showers

  • Juneteenth

    Juneteenth: Mostly sunny, with a high near 85. Calm wind becoming north around 5 mph in the afternoon.

    High: 85 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 62. Calm wind.

    Low: 62 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 87. Calm wind becoming south around 5 mph in the afternoon.

    High: 87 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 67. Calm wind.

    Low: 67 °F

    Mostly Clear
    then Chance
    Showers

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm. Partly sunny, with a high near 86. South wind 5 to 13 mph, with gusts as high as 24 mph.

    High: 86 °F

    Showers
    Likely

Detailed Forecast

Today
Sunny, with a high near 89. Breezy, with a south southwest wind 5 to 10 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 37 mph.
Tonight
Showers and thunderstorms likely before 4am, then a chance of showers. Increasing clouds, with a low around 74. Southwest wind 8 to 17 mph, with gusts as high as 33 mph. Chance of precipitation is 70%.
Thursday
A 30 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 87. West southwest wind around 6 mph becoming north northwest in the afternoon.
Thursday Night
A 30 percent chance of showers, mainly before 1am. Mostly cloudy, with a low around 64. Light north wind.
Juneteenth
Mostly sunny, with a high near 85. Calm wind becoming north around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 62. Calm wind.
Saturday
Mostly sunny, with a high near 87. Calm wind becoming south around 5 mph in the afternoon.
Saturday Night
A chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 67. Calm wind.
Sunday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 86. South wind 5 to 13 mph, with gusts as high as 24 mph.
Sunday Night
Showers and possibly a thunderstorm. Mostly cloudy, with a low around 70. Southwest wind 8 to 13 mph, with gusts as high as 22 mph.
Monday
A chance of showers and thunderstorms. Mostly cloudy, with a high near 84. West southwest wind around 10 mph becoming north northwest in the afternoon. Winds could gust as high as 21 mph.
Monday Night
A slight chance of showers and thunderstorms. Partly cloudy, with a low around 65. North wind around 6 mph becoming calm in the evening.
Tuesday
Mostly sunny, with a high near 83. Calm wind becoming north around 5 mph in the afternoon.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Simpson IL
 37.46°N 88.77°W
Last Update:
1:46 am CDT Jun 17, 2026
Forecast Valid:
8am CDT Jun 17, 2026-6pm CDT Jun 23, 2026
 
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