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Hazardous Weather Conditions

Current conditions at

Mount Vernon Airport (KMVN)

Lat: 38.33°NLon: 88.85°WElev: 466ft.

Fair

73°F

23°C

Humidity 94%
Wind Speed Calm
Barometer 30.00 in (1015.7 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 2 Sep 11:56 pm CDT
Extended Forecast for

Waltonville IL

Extreme Heat Warning September 3, 12:28am until September 5, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning September 3, 12:28am until September 5, 08:00pm

    NOW until 8:00pm Sat

    Extreme Heat Warning

  • Overnight

    Low: 76 °F

    Clear

  • Thursday

    Thursday: Sunny and hot, with a high near 99. Calm wind becoming southwest around 6 mph in the afternoon.

    High: 99 °F

    Hot

  • Thursday Night

    Thursday Night: Clear, with a low around 77. Calm wind.

    Low: 77 °F

    Clear

  • Friday

    Friday: Sunny and hot, with a high near 100. Heat index values as high as 106. Light southwest wind.

    High: 100 °F

    Hot

  • Friday Night

    Friday Night: Mostly clear, with a low around 76. Calm wind.

    Low: 76 °F

    Mostly Clear

  • Saturday

    Saturday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 98. Calm wind.

    High: 98 °F

    Sunny then
    Slight Chance
    T-storms

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 72. Calm wind.

    Low: 72 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 95. Calm wind becoming northeast around 6 mph in the afternoon.

    High: 95 °F

    Sunny

Detailed Forecast

Overnight
Clear, with a low around 76. Calm wind.
Thursday
Sunny and hot, with a high near 99. Calm wind becoming southwest around 6 mph in the afternoon.
Thursday Night
Clear, with a low around 77. Calm wind.
Friday
Sunny and hot, with a high near 100. Heat index values as high as 106. Light southwest wind.
Friday Night
Mostly clear, with a low around 76. Calm wind.
Saturday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny and hot, with a high near 98. Calm wind.
Saturday Night
Partly cloudy, with a low around 72. Calm wind.
Sunday
Sunny, with a high near 95. Calm wind becoming northeast around 6 mph in the afternoon.
Sunday Night
Mostly clear, with a low around 70. Northeast wind around 5 mph becoming calm in the evening.
Labor Day
Sunny, with a high near 94. Calm wind becoming east around 5 mph in the afternoon.
Monday Night
Mostly clear, with a low around 70. Light east wind.
Tuesday
Mostly sunny, with a high near 95. Calm wind becoming south southwest around 6 mph in the morning.
Tuesday Night
Mostly clear, with a low around 73. South wind 3 to 5 mph.
Wednesday
A slight chance of showers and thunderstorms. Sunny and hot, with a high near 97. Southwest wind 6 to 11 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Waltonville IL
 38.23°N 89.06°W
Last Update:
11:11 pm CDT Sep 2, 2026
Forecast Valid:
12am CDT Sep 3, 2026-6pm CDT Sep 9, 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