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

Marion - Williamson County Regional Airport (KMWA)

Lat: 37.77°NLon: 89.01°WElev: 486ft.

Fair

66°F

19°C

Humidity 49%
Wind Speed SW 6 mph
Barometer 29.88 in
Dewpoint 46°F (8°C)
Visibility 10.00 mi
Last update 5 Nov 4:47 pm CST
Extended Forecast for

Johnston City IL

  • Tonight

    Tonight: Increasing clouds, with a low around 45. West northwest wind 3 to 7 mph.

    Low: 45 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, then gradually becoming sunny, with a high near 56. North northwest wind 7 to 11 mph, with gusts as high as 21 mph.

    High: 56 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Widespread frost, mainly after 5am. Otherwise, clear, with a low around 32. North wind around 6 mph becoming calm in the evening.

    Low: 32 °F

    Mostly Clear
    then Frost

  • Saturday

    Saturday: Widespread frost, mainly before 8am. Otherwise, sunny, with a high near 56. Calm wind becoming north northwest around 6 mph.

    High: 56 °F

    Frost then
    Sunny

  • Saturday Night

    Saturday Night: Widespread frost, mainly after 4am. Otherwise, mostly clear, with a low around 31. Calm wind.

    Low: 31 °F

    Frost

  • Sunday

    Sunday: Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 62. Calm wind becoming west around 5 mph.

    High: 62 °F

    Frost then
    Sunny

  • Sunday Night

    Sunday Night: Patchy frost after 3am. Otherwise, clear, with a low around 35. Calm wind.

    Low: 35 °F

    Clear then
    Patchy Frost

  • Monday

    Monday: Patchy frost before 7am. Otherwise, sunny, with a high near 67. Calm wind becoming southwest 5 to 7 mph in the afternoon.

    High: 67 °F

    Patchy Frost
    then Sunny

  • Monday Night

    Monday Night: Clear, with a low around 38. Light west southwest wind.

    Low: 38 °F

    Clear

Detailed Forecast

Tonight
Increasing clouds, with a low around 45. West northwest wind 3 to 7 mph.
Friday
Mostly cloudy, then gradually becoming sunny, with a high near 56. North northwest wind 7 to 11 mph, with gusts as high as 21 mph.
Friday Night
Widespread frost, mainly after 5am. Otherwise, clear, with a low around 32. North wind around 6 mph becoming calm in the evening.
Saturday
Widespread frost, mainly before 8am. Otherwise, sunny, with a high near 56. Calm wind becoming north northwest around 6 mph.
Saturday Night
Widespread frost, mainly after 4am. Otherwise, mostly clear, with a low around 31. Calm wind.
Sunday
Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 62. Calm wind becoming west around 5 mph.
Sunday Night
Patchy frost after 3am. Otherwise, clear, with a low around 35. Calm wind.
Monday
Patchy frost before 7am. Otherwise, sunny, with a high near 67. Calm wind becoming southwest 5 to 7 mph in the afternoon.
Monday Night
Clear, with a low around 38. Light west southwest wind.
Tuesday
Sunny, with a high near 68. Calm wind becoming west around 6 mph.
Tuesday Night
Clear, with a low around 38. Calm wind.
Veterans Day
Sunny, with a high near 66. Calm wind becoming northwest around 6 mph.
Wednesday Night
Mostly clear, with a low around 39. Calm wind.
Thursday
Sunny, with a high near 64. Calm wind becoming northwest 5 to 8 mph in the morning.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Johnston City IL
 37.82°N 88.94°W
Last Update:
4:21 pm CST Nov 5, 2026
Forecast Valid:
5pm CST Nov 5, 2026-6pm CST Nov 12, 2026
 
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