Strong high pressure and elevated near surface moisture resulted in a multi-day heat wave across southeast South Dakota, southwest Minnesota, northwest Iowa, and northeast Nebraska from July 25-28. With air temperatures rising into the 90s and low 100s and dewpoint temperatures in the 70s and low 80s, afternoon and evening heat indices generally peaked from 100 to 120 degrees with little overnight recovery. The most widespread opressive conditions occurred during the afternoons and evenings of July 26 and July 27.

Excessive Heat in WOODBURY, IOWA
From 25-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 120 degrees with a maximum heat index of 120 degrees at the Iowa Department of Transportation site near Moville on July 27 and July 28.

Excessive Heat in LYON, IOWA
From 25-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Mesonet

Daily afternoon and evening heat indices ranged from 100 to 118 degrees with a maximum heat index of 118 degrees at the nearby South Dakota State University mesonet site near Baltic on July 27.

Excessive Heat in DICKINSON, IOWA
From 26-JUL-23 10:00:00 to 26-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the nearby Minnesota Department of Transportation site near Lakefield on July 26.

Excessive Heat in CLAY, IOWA
From 26-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Iowa Department of Transportation site near Spencer on July 26.

Excessive Heat in BUENA VISTA, IOWA
From 25-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 113 degrees with a maximum heat index of 113 degrees at the Iowa Department of Transportation site near Storm Lake on July 26.

Excessive Heat in CHEROKEE, IOWA
From 26-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Automated Weather Observation System site at Cherokee Regional Airport (KCKP) on July 28.

Excessive Heat in IDA, IOWA
From 26-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Afternoon and evening heat indices ranged from 100 to 112 degrees with a maximum heat index of 112 degrees at the Iowa Department of Transportation site near Ida Grove on July 28.

Excessive Heat in O'BRIEN, IOWA
From 25-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Automated Weather Observation System site at the Sheldon Regional Airport on July 26.

Excessive Heat in PLYMOUTH, IOWA
From 25-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: RAWS

Daily afternoon and evening heat indices ranged from 100 to 119 degrees with a maximum heat index of 119 degrees at the Remote Automatic Weather Station site near Elk Point on July 26 and July 27.

Excessive Heat in SIOUX, IOWA
From 25-JUL-23 10:00:00 to 28-JUL-23 22:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 114 degrees with a maximum heat index of 114 degrees at the Automated Weather Observation System site at the Sioux County Airport (KSXK) on July 27.

Excessive Heat in OSCEOLA, IOWA
From 26-JUL-23 10:00:00 to 26-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Afternoon and evening heat indices ranged from 100 to 109 degrees with a maximum heat index of 109 degrees at the Iowa Department of Transportation site near Sibley on July 26.