An unprecedented storm system lifted across the central Plains from December 15 into the early hours of December 16. Kinematic fields were at the top of the climatological distributions, leading to extreme wind shear in the lowest levels. Ahead of the system, record high temperatures with surface dew point values into the 50s and lower 60s surged toward northwest Iowa and resulted in instability not typically found in December.
A serial derecho developed across Nebraska and Kansas during the early afternoon and raced to the northeast toward Iowa and Minnesota, with widespread damaging wind and a few tornadoes.
As the cold front swung through the area behind the convective line, 60 to 75 mph winds aloft were mixed to the surface and resulted in a few synoptic wind gusts up to hurricane force. Some light wintry precipitation also fell during the transition toward the much colder air, which led to flash freezing as temperatures fell as much as 40 degrees during the overnight hours.

High Wind in DOUGLAS, SOUTH DAKOTA
From 15-DEC-21 20:00:00 to 15-DEC-21 23:00:00 (CST-6)
Magnitude: 51.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the late evening, with a peak wind gust of 59 mph at the South Dakota Road Weather Information System near Tripp (station SD570).

High Wind in YANKTON, SOUTH DAKOTA
From 15-DEC-21 18:30:00 to 15-DEC-21 23:05:00 (CST-6)
Magnitude: 50.00 MG
Reported by: ASOS

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 58 mph at the Yankton Municipal Airport (KYKN).

High Wind in MCCOOK, SOUTH DAKOTA
From 15-DEC-21 18:59:00 to 16-DEC-21 01:15:00 (CST-6)
Magnitude: 56.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening and into the overnight, with a peak wind gust of 65 mph at the South Dakota Road Weather Information System near Montrose (station SD547).

High Wind in AURORA, SOUTH DAKOTA
From 15-DEC-21 16:45:00 to 15-DEC-21 23:06:00 (CST-6)
Magnitude: 54.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 62 mph at the South Dakota Road Weather Information System near Plankinton (station SD553).

High Wind in MOODY, SOUTH DAKOTA
From 15-DEC-21 21:15:00 to 16-DEC-21 00:30:00 (CST-6)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening and into the overnight, with a peak wind gust of 63 mph at the South Dakota Road Weather Information System 13 miles west of Ward (station SD577).

High Wind in LAKE, SOUTH DAKOTA
From 15-DEC-21 19:15:00 to 15-DEC-21 22:55:00 (CST-6)
Magnitude: 56.00 MG
Reported by: AWOS

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 64 mph at the Madison Municipal Airport (KMDS). In addition, snowfall resulted in brief visibility restrictions below 1 mile, making travel difficult.

High Wind in GREGORY, SOUTH DAKOTA
From 15-DEC-21 15:50:00 to 16-DEC-21 04:12:00 (CST-6)
Magnitude: 64.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Sustained winds reached 40 to 60 mph during the evening and into the overnight, with a peak wind gust of 74 mph at the South Dakota Road Weather Information System at Fort Randall Dam (station SD588).

High Wind in BROOKINGS, SOUTH DAKOTA
From 15-DEC-21 21:20:00 to 15-DEC-21 23:15:00 (CST-6)
Magnitude: 37.00 MS
Reported by: AWOS

Sustained winds reached 43 mph at Brookings Municipal Airport (station KBKX).

High Wind in BON HOMME, SOUTH DAKOTA
From 15-DEC-21 17:55:00 to 15-DEC-21 18:10:00 (CST-6)
Magnitude: 55.00 MG
Reported by: Department of Highways

Sustained winds briefly reached near 40 mph during the evening, with a peak wind gust of 63 mph at the South Dakota Road Weather Information System near Tyndall (station SD571).

High Wind in MINNEHAHA, SOUTH DAKOTA
From 15-DEC-21 20:40:00 to 15-DEC-21 22:40:00 (CST-6)
Magnitude: 56.00 MG
Reported by: ASOS

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 64 mph at the Sioux Falls Airport (KFSD). In addition, light snowfall and a wintry mix resulted in brief visibility restrictions below 1 mile, making travel difficult.

High Wind in CHARLES MIX, SOUTH DAKOTA
From 15-DEC-21 15:34:00 to 15-DEC-21 23:25:00 (CST-6)
Magnitude: 60.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 55 mph during the evening, with a peak wind gust of 69 mph at the South Dakota Road Weather Information System at Platte-Winner Bridge (station SD554).

High Wind in SANBORN, SOUTH DAKOTA
From 15-DEC-21 18:00:00 to 15-DEC-21 23:00:00 (CST-6)
Magnitude: 51.00 MG
Reported by: Department of Highways

A peak gust of 59 mph was recorded at the South Dakota Road Weather Information System near Howard (station SD597). Sustained winds reached 40 to 50 mph at Mitchell (station KMHE) during the evening.

High Wind in CLAY, SOUTH DAKOTA
From 15-DEC-21 20:00:00 to 15-DEC-21 23:20:00 (CST-6)
Magnitude: 53.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 61 mph at the South Dakota Road Weather Information System near Gayville (station SD532).

High Wind in LINCOLN, SOUTH DAKOTA
From 15-DEC-21 19:39:00 to 16-DEC-21 00:00:00 (CST-6)
Magnitude: 60.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 69 mph at the South Dakota Road Weather Information System at Davis (station SD519).

High Wind in TURNER, SOUTH DAKOTA
From 15-DEC-21 19:35:00 to 16-DEC-21 00:00:00 (CST-6)
Magnitude: 55.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 63 mph at the South Dakota Road Weather Information System near Freeman (station SD530) and a peak wind gust of 69 mph at the South Dakota Road Weather Information System at Davis (station SD519).

High Wind in JERAULD, SOUTH DAKOTA
From 15-DEC-21 20:00:00 to 15-DEC-21 22:00:00 (CST-6)
Magnitude: 35.00 MS
Reported by: RAWS

Sustained winds reached around 40 mph during the evening at a site 13 miles south southwest of Wessington (station RHUS2).

High Wind in BRULE, SOUTH DAKOTA
From 15-DEC-21 19:35:00 to 15-DEC-21 21:15:00 (CST-6)
Magnitude: 37.00 MS
Reported by: AWOS

Sustained winds briefly reached 40 to 45 mph during the evening, with a peak wind gust of 54 mph at the Chamberlain Municipal Airport (K9V9). In addition, snowfall resulted in visibility restrictions below 1 mile, making travel difficult.

High Wind in DAVISON, SOUTH DAKOTA
From 15-DEC-21 17:45:00 to 15-DEC-21 22:55:00 (CST-6)
Magnitude: 55.00 MG
Reported by: ASOS

Sustained winds reached 40 to 46 mph during the evening, with a peak wind gust of 63 mph at the Mitchell Municipal Airport (KMHE). In addition, snow and a wintry mix resulted in visibility restrictions below 1 mile, making travel difficult.

High Wind in HUTCHINSON, SOUTH DAKOTA
From 15-DEC-21 20:50:00 to 15-DEC-21 23:26:00 (CST-6)
Magnitude: 55.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 63 mph at the South Dakota Road Weather Information System near Freeman (station SD530).

High Wind in KINGSBURY, SOUTH DAKOTA
From 15-DEC-21 22:00:00 to 16-DEC-21 00:15:00 (CST-6)
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Sustained winds reached 40 to 45 mph during the evening and into the overnight, with a peak wind gust of 60 mph at the South Dakota Road Weather Information System near Arlington (station SD504).

High Wind in HANSON, SOUTH DAKOTA
From 15-DEC-21 18:15:00 to 15-DEC-21 22:55:00 (CST-6)
Magnitude: 54.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 62 mph at the South Dakota Road Weather Information System near Alexandria (station SD502).

High Wind in BEADLE, SOUTH DAKOTA
From 15-DEC-21 18:30:00 to 15-DEC-21 23:30:00 (CST-6)
Magnitude: 54.00 MG
Reported by: ASOS

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 62 mph at the Huron Regional Airport (KHON). In addition, snowfall resulted in brief visibility restrictions below 1 mile, making travel difficult.

High Wind in UNION, SOUTH DAKOTA
From 15-DEC-21 20:20:00 to 16-DEC-21 00:15:00 (CST-6)
Magnitude: 56.00 MG
Reported by: Department of Highways

Sustained winds reached 40 to 50 mph during the evening and into the overnight, with a peak wind gust of 65 mph at the South Dakota Road Weather Information System near Beresford (station SD508).

High Wind in MINER, SOUTH DAKOTA
From 15-DEC-21 21:30:00 to 15-DEC-21 22:30:00 (CST-6)
Magnitude: 51.00 MG
Reported by: Department of Highways

A peak gust of 59 mph was recorded at the South Dakota Road Weather Information System near Howard (station SD597).