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.

Overcast

63°F

17°C

Humidity 77%
Wind Speed S 14 mph
Barometer 29.85 in
Dewpoint 55°F (13°C)
Visibility 10.00 mi
Last update 18 Nov 11:47 am CST
Extended Forecast for

Johnston City IL

  • This Afternoon

    This Afternoon: A 40 percent chance of showers and thunderstorms, mainly after 4pm. Mostly cloudy, with a high near 67. South southwest wind 8 to 11 mph, with gusts as high as 26 mph.

    High: 67 °F

    Chance
    Showers

  • Tonight

    Tonight: A 30 percent chance of showers before 7pm. Increasing clouds, with a low around 51. West southwest wind around 6 mph becoming calm in the evening.

    Low: 51 °F

    Chance
    Showers then
    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 63. North northwest wind around 5 mph becoming calm in the afternoon.

    High: 63 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: A 40 percent chance of showers after midnight. Mostly cloudy, with a low around 49. Calm wind.

    Low: 49 °F

    Mostly Cloudy
    then Chance
    Showers

  • Thursday

    Thursday: Showers. High near 63. Calm wind becoming south 5 to 7 mph in the morning. Chance of precipitation is 80%.

    High: 63 °F

    Showers

  • Thursday Night

    Thursday Night: Showers. Low around 55. South wind 3 to 5 mph. Chance of precipitation is 90%.

    Low: 55 °F

    Showers

  • Friday

    Friday: Showers. High near 65. East southeast wind 6 to 10 mph becoming west northwest in the afternoon. Chance of precipitation is 90%.

    High: 65 °F

    Showers

  • Friday Night

    Friday Night: Showers likely, mainly before midnight. Mostly cloudy, with a low around 46. North northeast wind around 7 mph.

    Low: 46 °F

    Showers
    Likely

  • Saturday

    Saturday: A slight chance of showers before noon. Mostly sunny, with a high near 60. North northeast wind 3 to 8 mph.

    High: 60 °F

    Slight Chance
    Showers then
    Mostly Sunny

Detailed Forecast

This Afternoon
A 40 percent chance of showers and thunderstorms, mainly after 4pm. Mostly cloudy, with a high near 67. South southwest wind 8 to 11 mph, with gusts as high as 26 mph.
Tonight
A 30 percent chance of showers before 7pm. Increasing clouds, with a low around 51. West southwest wind around 6 mph becoming calm in the evening.
Wednesday
Mostly cloudy, with a high near 63. North northwest wind around 5 mph becoming calm in the afternoon.
Wednesday Night
A 40 percent chance of showers after midnight. Mostly cloudy, with a low around 49. Calm wind.
Thursday
Showers. High near 63. Calm wind becoming south 5 to 7 mph in the morning. Chance of precipitation is 80%.
Thursday Night
Showers. Low around 55. South wind 3 to 5 mph. Chance of precipitation is 90%.
Friday
Showers. High near 65. East southeast wind 6 to 10 mph becoming west northwest in the afternoon. Chance of precipitation is 90%.
Friday Night
Showers likely, mainly before midnight. Mostly cloudy, with a low around 46. North northeast wind around 7 mph.
Saturday
A slight chance of showers before noon. Mostly sunny, with a high near 60. North northeast wind 3 to 8 mph.
Saturday Night
Mostly clear, with a low around 40. Calm wind.
Sunday
Sunny, with a high near 61. Calm wind becoming west southwest around 6 mph.
Sunday Night
Partly cloudy, with a low around 42. Calm wind becoming south southwest around 5 mph after midnight.
Monday
A slight chance of showers. Partly sunny, with a high near 61. South wind 5 to 9 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.91°W
Last Update:
10:31 am CST Nov 18, 2025
Forecast Valid:
12pm CST Nov 18, 2025-6pm CST Nov 24, 2025
 
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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