An immense ridge of high pressure over the Central Plains and Mississippi Valley entrenched heat and high dewpoint air across the region, resulting in daily heat indices from 100 to around 120, with very little recover during the overnight hours.

Excessive Heat in ROCK, MINNESOTA
From 21-AUG-23 11:00:00 to 24-AUG-23 18:00:00 (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 a personal weather station in Luverne on August 22, 114 degrees at a Minnesota Road Weather Information System site near Beaver Creek, 112 degrees near Magnolia, and 106 degrees at an Automated Weather Observing System site near Luverne on August 21.

Excessive Heat in PIPESTONE, MINNESOTA
From 21-AUG-23 11:00:00 to 23-AUG-23 21:00:00 (CST-6)
Reported by: RAWS

Daily afternoon and evening heat indices ranged from 102 to 111 degrees with a maximum heat index of 111 degrees at a RAWS site near Pipestone and 105 degrees at a Minnesota Road Weather Information System site near Trosky on August 21.

Excessive Heat in COTTONWOOD, MINNESOTA
From 21-AUG-23 11:00:00 to 24-AUG-23 18:00:00 (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 a Minnesota Road Weather Information System site near Mountain Lake, 109 degrees at an Automated Weather Observing System site near Windom, and 108 degrees at a Minnesota Road Weather Information System site near Jeffers on August 22.

Excessive Heat in LYON, MINNESOTA
From 21-AUG-23 11:00:00 to 23-AUG-23 21:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 119 degrees with a maximum heat index of 119 degrees at a personal weather station near Marshall, 118 degrees at an Automated Weather Observing System site at Tracy, and 109 degrees at Minnesota Road Weather Information System site at Taunton on August 22.

Excessive Heat in MURRAY, MINNESOTA
From 21-AUG-23 11:00:00 to 24-AUG-23 18:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 116 degrees with a maximum heat index of 116 degrees at an Automated Weather Observing System site at Slayton and 111 degrees at a Minnesota Road Weather Information System site near Dovray on August 22.

Excessive Heat in JACKSON, MINNESOTA
From 21-AUG-23 11:00:00 to 24-AUG-23 18:00:00 (CST-6)
Reported by: Mesonet

Daily afternoon and evening heat indices ranged from 100 to 125 degrees with a maximum heat index of 125 degrees at a personal weather station near Orleans, 123 degrees near Lakefield, and 118 degrees near Round Lake on August 22 and 23.

Excessive Heat in LINCOLN, MINNESOTA
From 21-AUG-23 11:00:00 to 23-AUG-23 21:00:00 (CST-6)
Reported by: Mesonet

Daily afternoon and evening heat indices ranged from 100 to 112 degrees with a maximum heat index of 112 degrees at a personal weather station near Ivanhoe and 107 degrees at a Minnesota Road Weather Information System site near Hendricks on August 21.

Excessive Heat in NOBLES, MINNESOTA
From 21-AUG-23 11:00:00 to 24-AUG-23 18:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 106 to 112 degrees with a maximum heat index of 112 degrees at an Automated Weather Observing System site at Worthington and 108 degrees at a Minnesota Road Weather Information System site near Rushmore on August 22.