Excessive heat and humidity invaded southern Illinois for the first time in the 2023 summer season. Peak heat indices were around 115 degrees at most locations on the 30th. On the 29th, thunderstorms kept most areas east of Interstate 57 relatively cool. However, the dangerous levels of heat and humidity encompassed the entire southern Illinois area on the 30th. Peak heat indices west of Interstate 57 on the 29th were around 110 degrees. The highest heat indices at selected cities on the 30th were 118 at Harrisburg, 115 at Marion, 114 at Metropolis, 113 at Carbondale, and 111 at Mt. Vernon.  The heat and humidity arrived on southwest winds ahead of a slow-moving cold front over western Missouri and northwest Illinois. Actual air temperatures exceeded 100 degrees in some places on the 30th, including 103 at Carbondale.

Excessive Heat in EDWARDS, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in WABASH, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in HAMILTON, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in WHITE, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in SALINE, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in GALLATIN, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in HARDIN, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in POPE, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in ALEXANDER, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in PULASKI, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in UNION, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in MASSAC, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in JOHNSON, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in WILLIAMSON, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in JACKSON, ILLINOIS
From 29-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in JEFFERSON, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in PERRY, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in FRANKLIN, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Excessive Heat in WAYNE, ILLINOIS
From 30-JUN-23 11:00:00 to 30-JUN-23 17:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS