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

70°F

21°C

Humidity 78%
Wind Speed S 17 G 28 mph
Barometer 29.89 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 4 Mar 6:47 pm CST
Extended Forecast for

Johnston City IL

Flood Watch until March 5, 12:00pm
Severe T-storm Watch until March 4, 09:00pm
Click here for hazard details and duration
Flood Watch
...
  •  
    Flood Watch until March 5, 12:00pm
    Severe T-storm Watch until March 4, 09:00pm

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Tonight

    Low: 61 °F

    Severe
    Thunderstorms
    then Showers
    and Patchy
    Fog

  • Thursday

    Thursday: Showers and possibly a thunderstorm, mainly before 10am, then a chance of showers and thunderstorms after 10am. High near 71. South southwest wind 6 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 90%.

    High: 71 °F

    Showers then
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 60. South wind 5 to 7 mph.

    Low: 60 °F

    Chance
    T-storms

  • Friday

    Friday: A slight chance of showers and thunderstorms between noon and 3pm, then a slight chance of showers after 3pm. Partly sunny, with a high near 78. South wind 8 to 16 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.

    High: 78 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Friday Night

    Friday Night: A slight chance of showers, then showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 62. South wind 11 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.

    Low: 62 °F

    Slight Chance
    Showers then
    Showers
    Likely

  • Saturday

    Saturday: Showers and possibly a thunderstorm. High near 69. South southwest wind 8 to 13 mph becoming northwest in the afternoon. Winds could gust as high as 21 mph. Chance of precipitation is 80%.

    High: 69 °F

    Showers then
    Chance
    Showers

  • Saturday Night

    Saturday Night: A 20 percent chance of showers before midnight. Mostly cloudy, with a low around 44. Northwest wind 5 to 7 mph becoming calm in the evening.

    Low: 44 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 65. Calm wind becoming south around 5 mph.

    High: 65 °F

    Mostly Sunny

Detailed Forecast

Tonight
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 11pm. Some of the storms could be severe. Patchy fog after 5am. Low around 61. South southwest wind 6 to 9 mph. Chance of precipitation is 90%.
Thursday
Showers and possibly a thunderstorm, mainly before 10am, then a chance of showers and thunderstorms after 10am. High near 71. South southwest wind 6 to 11 mph, with gusts as high as 20 mph. Chance of precipitation is 90%.
Thursday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 60. South wind 5 to 7 mph.
Friday
A slight chance of showers and thunderstorms between noon and 3pm, then a slight chance of showers after 3pm. Partly sunny, with a high near 78. South wind 8 to 16 mph, with gusts as high as 25 mph. Chance of precipitation is 20%.
Friday Night
A slight chance of showers, then showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 62. South wind 11 to 14 mph, with gusts as high as 24 mph. Chance of precipitation is 70%.
Saturday
Showers and possibly a thunderstorm. High near 69. South southwest wind 8 to 13 mph becoming northwest in the afternoon. Winds could gust as high as 21 mph. Chance of precipitation is 80%.
Saturday Night
A 20 percent chance of showers before midnight. Mostly cloudy, with a low around 44. Northwest wind 5 to 7 mph becoming calm in the evening.
Sunday
Mostly sunny, with a high near 65. Calm wind becoming south around 5 mph.
Sunday Night
Mostly clear, with a low around 49. South southwest wind 3 to 5 mph.
Monday
A slight chance of showers and thunderstorms after noon. Mostly sunny, with a high near 76. South southwest wind 5 to 11 mph, with gusts as high as 18 mph.
Monday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 62. South southwest wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Showers and thunderstorms likely. Mostly cloudy, with a high near 78. South southwest wind 11 to 17 mph, with gusts as high as 26 mph.
Tuesday Night
Showers and possibly a thunderstorm. Cloudy, with a low around 53. South southwest wind 15 to 17 mph, with gusts as high as 26 mph.
Wednesday
Showers likely. Mostly cloudy, with a high near 63. South southwest wind around 16 mph becoming west northwest in the afternoon. Winds could gust as high as 25 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.91°W
Last Update:
7:21 pm CST Mar 4, 2026
Forecast Valid:
7pm CST Mar 4, 2026-6pm CDT Mar 11, 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