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 LAKE, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 110 degrees with a maximum heat index of 110 degrees at the Automated Weather Observation System site at the Madison Municipal Airport on July 27.

Excessive Heat in LINCOLN, SOUTH DAKOTA
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 121 degrees with a maximum heat index of 121 degrees at the Automated Weather Observation System site at the Marv Skie Lincoln County Airport on July 26.

Excessive Heat in MINER, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 107 degrees with a maximum heat index of 107 degrees at the South Dakota Road Weather Information System site near Howard on July 27.

Excessive Heat in HUTCHINSON, SOUTH DAKOTA
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 113 degrees with a maximum heat index of 113 degrees at the South Dakota State University mesonet site near Parkston on July 27.

Excessive Heat in YANKTON, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: AWOS

Daily afternoon and evening heat indices ranged from 100 to 106 degrees with a maximum heat index of 106 degrees at the Automated Weather Observation System site at the Yankton Municipal Airport (KYKN) on July 26 and July 27.

Excessive Heat in SANBORN, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 109 degrees with a maximum heat index of 109 degrees at the South Dakota Road Weather Information System site near Forestburg on July 26 and July 27.

Excessive Heat in MCCOOK, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-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 nearby South Dakota Road Weather Information System site near Alexandria on July 26.

Excessive Heat in MINNEHAHA, SOUTH DAKOTA
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 South Dakota State University mesonet site near Baltic on July 27.

Excessive Heat in MOODY, SOUTH DAKOTA
From 26-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 110 degrees with a maximum heat index of 110 degrees at the South Dakota State University meonet site near Flandreau on July 27.

Excessive Heat in TURNER, SOUTH DAKOTA
From 26-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 108 degrees with a maximum heat index of 108 degrees at the nearby South Dakota State University mesonet site near Beresford on July 27.

Excessive Heat in CHARLES MIX, SOUTH DAKOTA
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 119 degrees with a maximum heat index of 119 degrees at the Automated Weather Observation System site at the Wagner Municipal Airport (KAGZ) on July 27.

Excessive Heat in CLAY, SOUTH DAKOTA
From 26-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 108 degrees with a maximum heat index of 108 degrees at the South Dakota State University mesonet site near Beresford on July 27.

Excessive Heat in DOUGLAS, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 107 degrees with a maximum heat index of 107 degrees at the South Dakota Road Weather Information System site near Corsica on July 27.

Excessive Heat in UNION, SOUTH DAKOTA
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 112 degrees with a maximum heat index of 112 degrees at the South Dakota Road Weather Information System site near North Sioux City on July 26 and July 27.

Excessive Heat in AURORA, SOUTH DAKOTA
From 25-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 108 degrees with a maximum heat index of 108 degrees at the South Dakota Road Weather Information System site near Plankinton on July 27.

Excessive Heat in BEADLE, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 108 degrees with a maximum heat index of 108 degrees at the South Dakota Road Weather Information System site near Cavour on July 27.

Excessive Heat in BRULE, SOUTH DAKOTA
From 25-JUL-23 10:00:00 to 25-JUL-23 22:00:00 (CST-6)
Reported by: ASOS

Afternoon and evening heat indices ranged from 100 to 107 degrees with a maximum heat index of 107 degrees at the Automated Surface Observation System site at the Chamberlain Municipal Airport (K9V9) on July 25.

Excessive Heat in BON HOMME, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 107 degrees with a maximum heat index of 107 degrees at the South Dakota Road Weather Information System site near Tyndall on July 27.

Excessive Heat in BROOKINGS, SOUTH DAKOTA
From 27-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Mesonet

Afternoon and evening heat indices ranged from 100 to 109 degrees with a maximum heat index of 109 degrees at the South Dakota State University mesonet site near Volga on July 27.

Excessive Heat in JERAULD, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 112 degrees with a maximum heat index of 112 degrees at the South Dakota Road Weather Information System site near Lane on July 27.

Excessive Heat in KINGSBURY, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: Department of Highways

Daily afternoon and evening heat indices ranged from 100 to 117 degrees with a maximum heat index of 117 degrees at the South Dakota Road Weather Information System site near Arlington on July 27.

Excessive Heat in DAVISON, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-JUL-23 22:00:00 (CST-6)
Reported by: ASOS

Daily afternoon and evening heat indices ranged from 100 to 108 degrees with a maximum heat index of 108 degrees at the Automated Surface Observation System site at the Mitchell Municipal Airport (KMHE) on July 27.

Excessive Heat in GREGORY, SOUTH DAKOTA
From 25-JUL-23 10:00:00 to 25-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 South Dakota Road Weather Information System site at the Fort Randall Dam on July 25.

Excessive Heat in HANSON, SOUTH DAKOTA
From 26-JUL-23 10:00:00 to 27-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 South Dakota Road Weather Information System site near Alexandria on July 26.