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

Hazardous Weather Conditions

Current conditions at

Mount Vernon Airport (KMVN)

Lat: 38.33°NLon: 88.85°WElev: 466ft.

Fair

100°F

38°C

Humidity 34%
Wind Speed S 10 mph
Barometer 30.00 in (1015.6 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index105°F (41°C)
Last update 1 Sep 4:56 pm CDT
Extended Forecast for

Nason IL

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

    NOW until 8:00pm Sat

    Extreme Heat Warning

  • This Afternoon

    High: 100 °F

    Hot

  • Tonight

    Tonight: Clear, with a low around 77. Light south wind.

    Low: 77 °F

    Clear

  • Wednesday

    Wednesday: Sunny and hot, with a high near 101. Heat index values as high as 107. Calm wind becoming south southwest 5 to 7 mph in the afternoon.

    High: 101 °F

    Hot

  • Wednesday Night

    Wednesday Night: Clear, with a low around 77. South wind around 5 mph becoming calm in the evening.

    Low: 77 °F

    Clear

  • Thursday

    Thursday: Sunny and hot, with a high near 100. Calm wind becoming southwest 5 to 7 mph in the afternoon.

    High: 100 °F

    Hot

  • Thursday Night

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

    Low: 77 °F

    Clear

  • Friday

    Friday: Sunny and hot, with a high near 100. Light and variable wind.

    High: 100 °F

    Hot

  • Friday Night

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

    Low: 76 °F

    Mostly Clear

Detailed Forecast

This Afternoon
Sunny and hot, with a high near 100. Light south wind.
Tonight
Clear, with a low around 77. Light south wind.
Wednesday
Sunny and hot, with a high near 101. Heat index values as high as 107. Calm wind becoming south southwest 5 to 7 mph in the afternoon.
Wednesday Night
Clear, with a low around 77. South wind around 5 mph becoming calm in the evening.
Thursday
Sunny and hot, with a high near 100. Calm wind becoming southwest 5 to 7 mph in the afternoon.
Thursday Night
Clear, with a low around 77. Light south wind.
Friday
Sunny and hot, with a high near 100. Light and variable wind.
Friday Night
Mostly clear, with a low around 76. Calm wind.
Saturday
A slight chance of showers and thunderstorms. Sunny and hot, with a high near 100. Calm wind.
Saturday Night
Partly cloudy, with a low around 73. Calm wind.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 96. Calm wind becoming north 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 93. Calm wind becoming east around 6 mph in the afternoon.
Monday Night
Partly cloudy, with a low around 68. East wind 3 to 6 mph.
Tuesday
Mostly sunny, with a high near 93. Light and variable wind becoming south southwest around 6 mph in the morning.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Nason IL
 38.18°N 88.98°W
Last Update:
1:26 pm CDT Sep 1, 2026
Forecast Valid:
5pm CDT Sep 1, 2026-6pm CDT Sep 8, 2026
 
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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