Warm and humid air invaded northeast Iowa on July 17th and remained in place for the next three days. During this stretch, afternoon heat indices routinely topped out between 110 and 120. Little relief occurred at night, as overnight lows remained in the 70s. The heat caused four people to visit the emergency room in Allamakee County and a farmer lost several head of cattle in Mitchell County. Most of the counties across northeast Iowa also opened cooling centers.

Excessive Heat in MITCHELL, IOWA
From 17-JUL-11 14:00:00 to 20-JUL-11 20:30:00 (CST-6)
Property damage: 69.70K
Crop damage: 0.00K
Reported by: Emergency Manager

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees. One farmer lost 27 head of cattle from the heat.

Excessive Heat in WINNESHIEK, IOWA
From 17-JUL-11 14:00:00 to 20-JUL-11 18:00:00 (CST-6)
Property damage: 35.00K
Crop damage: 0.00K
Reported by: AWOS

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees. The highest recored heat index at Decorah was 114 on the 19th.

Excessive Heat in ALLAMAKEE, IOWA
From 17-JUL-11 14:30:00 to 20-JUL-11 17:00:00 (CST-6)
Property damage: 22.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Four people had to visit the emergency room because of illness caused by the excessive heat. For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees.

Excessive Heat in FAYETTE, IOWA
From 17-JUL-11 14:30:00 to 20-JUL-11 18:00:00 (CST-6)
Property damage: 27.00K
Crop damage: 0.00K
Reported by: Unknown

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees.

Excessive Heat in HOWARD, IOWA
From 17-JUL-11 15:00:00 to 20-JUL-11 20:00:00 (CST-6)
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Unknown

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees.

Excessive Heat in CHICKASAW, IOWA
From 17-JUL-11 15:00:00 to 20-JUL-11 20:00:00 (CST-6)
Property damage: 33.00K
Crop damage: 0.00K
Reported by: Unknown

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees.

Excessive Heat in CLAYTON, IOWA
From 17-JUL-11 14:00:00 to 20-JUL-11 17:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Unknown

For an extended period between the 17th and 20th, afternoon heat indices routinely topped out between 110 and 115 with overnight low temperatures remaining above 75 degrees.  The highest heat index at Dubuque, IA was on the 19th with 114.

Excessive Heat in FLOYD, IOWA
From 17-JUL-11 16:30:00 to 20-JUL-11 22:00:00 (CST-6)
Property damage: 45.00K
Crop damage: 0.00K
Reported by: AWOS

For an extended period between the 17th and 20th, afternoon heat indices were routinely between 110 and 115 with overnight low temperatures remaining at or above 75 degrees. The highest heat index recorded at Charles City was 117 on both the 18th and 19th.