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Summary of June 21, 2026 Tornadoes

Hazardous Weather Conditions

Current conditions at

Mount Vernon Airport (KMVN)

Lat: 38.33°NLon: 88.85°WElev: 466ft.

76°F

24°C

Humidity	94%
Wind Speed	S 5 mph
Barometer	29.93 in (1013.4 mb)
Dewpoint	74°F (23°C)
Visibility	10.00 mi
Heat Index	76°F (24°C)
Last update	29 Jun 2:56 am CDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

3 Miles W Mount Vernon IL

Extreme Heat Warning June 29, 11:00am until July 3, 08:00pm

Click here for hazard details and duration

Extreme Heat Warning

Overnight
Low: 74 °F
Mostly Clear
Monday
High: 95 °F
Mostly Sunny
Monday Night
Low: 75 °F
Mostly Clear
Tuesday
High: 96 °F
Sunny
Tuesday Night
Low: 74 °F
Clear
Wednesday
High: 97 °F
Hot
Wednesday Night
Low: 76 °F
Clear
Thursday
High: 98 °F
Hot
Thursday Night
Low: 77 °F
Mostly Clear

Detailed Forecast

Overnight

Mostly clear, with a low around 74. Light south wind.

Monday

Mostly sunny, with a high near 95. Heat index values as high as 109. Light south wind increasing to 6 to 11 mph in the morning. Winds could gust as high as 18 mph.

Monday Night

Mostly clear, with a low around 75. South wind 5 to 9 mph becoming light south southwest after midnight.

Tuesday

Sunny, with a high near 96. Heat index values as high as 109. Calm wind becoming south southwest 5 to 8 mph in the morning.

Tuesday Night

Clear, with a low around 74. South wind 5 to 7 mph becoming calm in the evening.

Wednesday

Sunny and hot, with a high near 97. Calm wind becoming south southwest around 5 mph in the afternoon.

Wednesday Night

Clear, with a low around 76. Light south wind.

Thursday

Sunny and hot, with a high near 98. Light and variable wind.