Johnston City, Illinois Weather
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Weather Forecast for Johnston City, Illinois : Williamson County
Issued: 12:01 am CDT Sep 16, 2025 Latitude: 37.8206053 Longitude: -88.9275695 View on Google Maps

MouseOver for Detail Forecast
Overnight Tuesday Wednesday Thursday Friday Saturday Sunday Monday
Mostly Clear on Overnight Sunny on Tuesday Sunny on Wednesday Sunny on Thursday 20% chance of thunderstorms on Friday 20% chance of thunderstorms on Saturday 20% chance of thunderstorms on Sunday 10% chance of thunderstorms on Monday
Low: 67°F High: 93°F High: 93°F High: 95°F High: 88°F High: 88°F High: 87°F High: 85°F
Low: 64°F Low: 63°F Low: 66°F Low: 65°F Low: 64°F Low: 64°F  
Mostly Clear Sunny Sunny Sunny Thunderstorms Thunderstorms Thunderstorms Thunderstorms
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Current Conditions at
MARION - (KMWA)
68°
Clear
as of 12:55 AM CDST
Rel. Humidity: 93%
Dew Point: 66°F
Visibility: 10 Miles
Pressure: 30.09 in.
Flight Rule: VFR
Wind Data
Calm
Cloud Level(s): Clear
Current Conditions at
CARBONDALE - (KMDH)
66°
Clear
as of 12:52 AM CDST
Rel. Humidity: 100%
Dew Point: 66°F
Visibility: 10 Miles
Pressure: 30.08 in.
Flight Rule: VFR
Wind Data
Calm
Cloud Level(s): Clear
Current Conditions at
HARRISBURG-RALEIGH - (KHSB)
68°
Clear
as of 12:55 AM CDST
Rel. Humidity: 82%
Dew Point: 63°F
Visibility: 10 Miles
Pressure: 30.09 in.
Flight Rule: VFR
Wind Data
Calm
Cloud Level(s): Clear
Current Conditions at
MT VERNON - (KMVN)
70°
Clear
as of 12:56 AM CDST
Rel. Humidity: 83%
Dew Point: 64°F
Visibility: 10 Miles
Pressure: 30.10 in.
Flight Rule: VFR
Wind Data
5 MPH
010° North
Cloud Level(s): Clear
Mostly Clear on Overnight Overnight... Mostly clear, with a low around 67. Calm wind.
Sunny on Tuesday Tuesday... Sunny, with a high near 93. Calm wind becoming northeast 5 to 7 mph in the afternoon.
Mostly Clear on Tuesday Night Tuesday Night... Mostly clear, with a low around 64. East northeast wind around 5 mph becoming calm in the evening.
Sunny on Wednesday Wednesday... Sunny, with a high near 93. Light east northeast wind.
Mostly Clear on Wednesday Night Wednesday Night... Mostly clear, with a low around 63. Calm wind.
Sunny on Thursday Thursday... Sunny, with a high near 95. Calm wind becoming south around 6 mph in the afternoon.
Cloudy on Thursday Night Thursday Night... Partly cloudy, with a low around 66. Light south southeast wind.
20% chance of thunderstorms Friday Friday... A chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 88. Calm wind becoming southwest around 6 mph in the afternoon.
20% chance of thunderstorms Friday Night Friday Night... A chance of showers and thunderstorms. Mostly cloudy, with a low around 65. Light south southeast wind.
20% chance of thunderstorms Saturday Saturday... A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88. Calm wind becoming south 5 to 7 mph in the morning.
20% chance of thunderstorms Saturday Night Saturday Night... A chance of showers and thunderstorms. Partly cloudy, with a low around 64. Light south southwest wind.
20% chance of thunderstorms Sunday Sunday... A chance of showers and thunderstorms. Mostly sunny, with a high near 87. Calm wind becoming south southwest 5 to 9 mph in the morning.
20% chance of thunderstorms Sunday Night Sunday Night... A chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Light south wind.
10% chance of thunderstorms Monday Monday... A slight chance of showers and thunderstorms. Mostly sunny, with a high near 85. South southwest wind 3 to 8 mph.
Current Radar Image


Sun Almanac for Johnston City, Illinois
Sunrise: 06:39 AM
Sunset: 7:02 PM
Civil Sunrise:06:13 AM
Civil Sunset: 7:28 PM
Nautical Sunrise: 05:42 AM
Nautical Sunset: 7:59 PM
Astro Sunrise: 05:10 AM
Astro Sunset: 8:31 PM
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