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Hazardous Weather Conditions

Current conditions at

Mount Vernon Airport (KMVN)

Lat: 38.33°NLon: 88.85°WElev: 466ft.

Fair

92°F

33°C

Humidity 56%
Wind Speed SW 12 mph
Barometer 30.00 in (1015.6 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index102°F (39°C)
Last update 11 Aug 11:56 am CDT
Extended Forecast for

Waltonville IL

Heat Advisory August 11, 12:34pm until August 13, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 11, 12:34pm until August 13, 08:00pm

    NOW until 8:00pm Thu

    Heat Advisory

  • This Afternoon

    High: 97 °F

    Hot

  • Tonight

    Tonight: Mostly clear, with a low around 76. South southwest wind 6 to 9 mph.

    Low: 76 °F

    Mostly Clear

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms, mainly before 4pm. Mostly sunny, with a high near 96. Heat index values as high as 107. Southwest wind 5 to 7 mph.

    High: 96 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms, mainly between 3am and 4am. Mostly cloudy, then gradually becoming clear, with a low around 76. West wind around 6 mph becoming south in the evening.

    Low: 76 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: Mostly sunny, with a high near 96. Southwest wind 3 to 6 mph.

    High: 96 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 76. South wind 3 to 6 mph.

    Low: 76 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 95. Light and variable wind.

    High: 95 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 75. East wind 3 to 5 mph.

    Low: 75 °F

    Mostly Clear

Detailed Forecast

This Afternoon
Sunny and hot, with a high near 97. Heat index values as high as 107. West northwest wind 6 to 9 mph becoming southwest.
Tonight
Mostly clear, with a low around 76. South southwest wind 6 to 9 mph.
Wednesday
A 30 percent chance of showers and thunderstorms, mainly before 4pm. Mostly sunny, with a high near 96. Heat index values as high as 107. Southwest wind 5 to 7 mph.
Wednesday Night
A 20 percent chance of showers and thunderstorms, mainly between 3am and 4am. Mostly cloudy, then gradually becoming clear, with a low around 76. West wind around 6 mph becoming south in the evening.
Thursday
Mostly sunny, with a high near 96. Southwest wind 3 to 6 mph.
Thursday Night
Partly cloudy, with a low around 76. South wind 3 to 6 mph.
Friday
Mostly sunny, with a high near 95. Light and variable wind.
Friday Night
Mostly clear, with a low around 75. East wind 3 to 5 mph.
Saturday
Sunny and hot, with a high near 98. Light and variable wind becoming south around 5 mph.
Saturday Night
Mostly clear, with a low around 76. Calm wind becoming south around 6 mph in the evening.
Sunday
Sunny and hot, with a high near 99. Light southwest wind becoming west 5 to 9 mph in the morning.
Sunday Night
Mostly clear, with a low around 74. Calm wind.
Monday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 91. Calm wind becoming north around 5 mph in the afternoon.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Waltonville IL
 38.2°N 89.03°W
Last Update:
12:06 pm CDT Aug 11, 2026
Forecast Valid:
12pm CDT Aug 11, 2026-6pm CDT Aug 17, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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