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. The first Storm Prediction Center moderate risk, as well as severe thunderstorm and tornado warnings during December, were issued for the Sioux Falls warning area. There was even remaining snow cover in parts of northwest Iowa north of Highway 18 and into southwest Minnesota as the severe storms evolved during the afternoon and evening hours.
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.

Tornado in PLYMOUTH, IOWA
From 15-DEC-21 16:39:00 to 15-DEC-21 16:42:00 (CST-6)
Location: KINGSLEY
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado formed around 4 miles east-northeast of Moville in Woodbury County and entered Plymouth County around two miles south of Kingsley, just east of the intersection of Knox Avenue and 100th Street.  Numerous large trees were snapped as the tornado entered Plymouth County. The tornado continued to travel north-northeast to a location around one mile east of Kingsley where several outbuildings were destroyed and large trees snapped.  The tornado then turned to a northerly track as it crossed County Road C66, where it damaged several power poles.  The tornado traveled another mile and a half parallel to Roosevelt Avenue before it destroyed a hoop barn and removed the steel roof from a corn crib, with debris scattered a half mile to the north.  The tornado dissipated after another quarter mile at 1642CST. The tornado was rated EF1 while in both Woodbury and Plymouth Counties. The average path width in Plymouth County was 50 yards and the maximum estimated wind speed was 105 mph. Property damage costs are a rough estimate.

Tornado in WOODBURY, IOWA
From 15-DEC-21 16:15:00 to 15-DEC-21 16:16:00 (CST-6)
Location: SALIX
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A public video revealed that a tornado briefly spun up in an open field southwest of Salix between Benton Avenue and Interstate 29 north of 290th Street. The tornado traveled north northeast and lifted just south of 280th Street. The average path width was estimated at 20 yards.

High Wind in OSCEOLA, IOWA
From 15-DEC-21 21:00:00 to 16-DEC-21 01:00:00 (CST-6)
Magnitude: 37.00 MS
Reported by: Mesonet

Sustained winds reached 43 mph at station SBEI4 6 miles west southwest of Ocheyedan.

Thunderstorm Wind in DICKINSON, IOWA
From 15-DEC-21 17:52:00 to 15-DEC-21 17:53:00 (CST-6)
Location: SUPERIOR
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Large branches were downed by thunderstorm wind gusts. Numerous shingles were blown off the roof, and the garage was blown off its foundation. Property damage costs are a rough estimate.

High Wind in O'BRIEN, IOWA
From 15-DEC-21 20:35:00 to 16-DEC-21 00:00:00 (CST-6)
Magnitude: 54.00 MG
Reported by: AWOS

Sustained winds reached 40 to 50 mph during the evening, with a peak wind gust of 62 mph at the Sheldon Regional Airport (KSHL).

High Wind in BUENA VISTA, IOWA
From 15-DEC-21 21:00:00 to 16-DEC-21 01:00:00 (CST-6)
Magnitude: 59.00 MG
Reported by: AWOS

Sustained winds reached 40 to 52 mph during the evening and into the early overnight, with a peak wind gust of 68 mph at the Storm Lake Airport (KSLB).

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 17:02:00 to 15-DEC-21 17:03:00 (CST-6)
Location: AURELIA
Magnitude: 87.00 EG
Reported by: NWS Storm Survey

Three empty railcars were blown over by thunderstorm winds.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:41:00 to 15-DEC-21 16:42:00 (CST-6)
Location: KINGSLEY
Magnitude: 74.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

An old barn was destroyed by thunderstorms winds. Property damage costs are a rough estimate.

High Wind in DICKINSON, IOWA
From 15-DEC-21 22:00:00 to 15-DEC-21 22:15:00 (CST-6)
Magnitude: 51.00 MG
Reported by: Mesonet

Sustained winds briefly approached 40 mph during the evening, with a peak wind gust of 59 mph at a Citizen Weather Observer Program (CWOP) station near Milford.

High Wind in CLAY, IOWA
From 15-DEC-21 20:45:00 to 16-DEC-21 01:00:00 (CST-6)
Magnitude: 63.00 MG
Reported by: ASOS

Sustained winds reached 40 to 52 mph during the evening and into the early overnight, with a peak wind gust of 72 mph at the Spencer Municipal Airport (KSPW).

High Wind in CHEROKEE, IOWA
From 15-DEC-21 20:40:00 to 15-DEC-21 23:45:00 (CST-6)
Magnitude: 39.00 MS
Reported by: Mesonet

Sustained winds reached 45 mph at station MCSI4 near 10 miles south of Marcus.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:38:00 to 15-DEC-21 16:39:00 (CST-6)
Location: KINGSLEY
Magnitude: 72.00 EG
Reported by: NWS Storm Survey

An old barn was pushed off its foundation and partially collapsed.

Thunderstorm Wind in O'BRIEN, IOWA
From 15-DEC-21 17:11:00 to 15-DEC-21 17:12:00 (CST-6)
Location: SUTHERLAND
Magnitude: 65.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds snapped several large trees and limbs, which fell and destroyed the roof of a machine shed. Property damage costs are a rough estimate.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:23:00 to 15-DEC-21 17:25:00 (CST-6)
Location: ROYAL
Magnitude: 70.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm winds knocked down an old barn, with several other outbuildings damaged. Property damage costs are a rough estimate.

High Wind in PLYMOUTH, IOWA
From 15-DEC-21 20:35:00 to 15-DEC-21 20:55:00 (CST-6)
Magnitude: 55.00 MG
Reported by: AWOS

Sustained winds briefly reached around 40 mph during the evening, with a peak wind gust of 63 mph at Le Mars Municipal Airport (KLRJ).

High Wind in SIOUX, IOWA
From 15-DEC-21 19:55:00 to 15-DEC-21 23:55:00 (CST-6)
Magnitude: 58.00 MG
Reported by: AWOS

Sustained winds reached 40 to 59 mph during the evening, with a peak wind gust of 67 mph at the Sioux County Regional Airport (KSKX).

High Wind in LYON, IOWA
From 15-DEC-21 21:00:00 to 15-DEC-21 23:00:00 (CST-6)
Magnitude: 40.00 MS
Reported by: Mesonet

Sustained winds reached 46 mph at station DONI4 near Doon.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 17:03:00 to 15-DEC-21 17:04:00 (CST-6)
Location: AURELIA
Magnitude: 78.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds resulted in failure of garage doors, with removal of walls and roof of half the building. Debris was thrown north and northwest into several homes. Property damage costs are a rough estimate.

Thunderstorm Wind in DICKINSON, IOWA
From 15-DEC-21 17:49:00 to 15-DEC-21 17:50:00 (CST-6)
Location: SPIRIT LAKE
Magnitude: 65.00 EG
Property damage: 10.00K
Reported by: Public

Thunderstorm winds downed several power poles. Property damage costs are a rough estimate.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 16:46:00 to 15-DEC-21 16:47:00 (CST-6)
Location: FIELDING
Magnitude: 74.00 EG
Reported by: NWS Storm Survey

Thunderstorm winds caused the collapse of a brick gable on the west side of a building at the Grand Meadow Heritage Center, as well as lesser damage to other buildings. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:47:00 to 15-DEC-21 16:48:00 (CST-6)
Location: KINGSLEY
Magnitude: 64.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds removed numerous metal panels from a shed roof. Property damage costs are a rough estimate.

Thunderstorm Wind in BUENA VISTA, IOWA
From 15-DEC-21 17:08:00 to 15-DEC-21 17:09:00 (CST-6)
Location: STORM LAKE ARPT
Magnitude: 66.00 EG
Reported by: NWS Storm Survey

A large tree was uprooted by thunderstorm winds.

Thunderstorm Wind in BUENA VISTA, IOWA
From 15-DEC-21 17:01:00 to 15-DEC-21 17:02:00 (CST-6)
Location: HANOVER
Magnitude: 64.00 EG
Reported by: NWS Storm Survey

Several large branches were downed by thunderstorm winds.

High Wind in WOODBURY, IOWA
From 15-DEC-21 20:20:00 to 15-DEC-21 22:20:00 (CST-6)
Magnitude: 58.00 MG
Reported by: ASOS

Sustained winds reached 40 to 45 mph during the evening, with a peak wind gust of 67 mph at the Sioux Gateway Airport (KSUX).

High Wind in IDA, IOWA
From 15-DEC-21 20:30:00 to 16-DEC-21 00:00:00 (CST-6)
Magnitude: 59.00 MG
Reported by: AWOS

Sustained winds reached 40 to 52 mph during the evening and into the early overnight, with a peak wind gust of 68 mph at the Storm Lake Airport (KSLB).

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:44:00 to 15-DEC-21 16:45:00 (CST-6)
Location: KINGSLEY
Magnitude: 69.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds damaged the top section of a barn, also leaning toward the north. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:44:00 to 15-DEC-21 16:45:00 (CST-6)
Location: KINGSLEY
Magnitude: 65.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds caused extensive damage to an outbuilding with an open side toward the southeast. Property damage costs are a rough estimate.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 16:53:00 to 15-DEC-21 16:54:00 (CST-6)
Location: MARY HILL
Magnitude: 83.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds knocked down a machine shed. Property damage costs are a rough estimate.

Tornado in O'BRIEN, IOWA
From 15-DEC-21 17:08:00 to 15-DEC-21 17:11:00 (CST-6)
Location: CALUMET
Tornado F-scale: EF1
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado formed on the southeast edge of Larrabee in Cherokee County, just south of 455th Street. The tornado entered O'Brien County around 4 miles south of Sutherland, one-half mile east of the intersection of Tyler Avenue and 420th Street. The tornado continued northeast in O'Brien County for almost 4 miles, and resulted in only sporadic tree damage before destroying a shed and scattered debris across State Highway 10 two miles south-southeast of Sutherland. The tornado tore part of a roof off a shed shortly before it dissipated two miles southeast of Sutherland at 1711CST. The tornado was rated EF1 while in both Cherokee County and O'Brien County. The average path width in O'Brien County was 75 yards and the maximum estimated wind speed was 105 mph. Property damage costs are a rough estimate.

Tornado in WOODBURY, IOWA
From 15-DEC-21 16:20:00 to 15-DEC-21 16:24:00 (CST-6)
Location: SALIX
Tornado F-scale: EF1
Property damage: 250.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado touched down near Buchanan Avenue between 230th and 240th streets and moved north northeast, impacting four farmsteads. One machine shed was completely destroyed with debris deposited about 1 mile downstream in an open field. Several other outbuildings were damaged along the track along with a few trees. The tornado lifted just east of the intersection of Old Highway 141 and County Home Road. The average path width was 50 yards and the maximum estimated wind speed was 105 mph. Property damage costs are a rough estimate.

Tornado in WOODBURY, IOWA
From 15-DEC-21 16:25:00 to 15-DEC-21 16:32:00 (CST-6)
Location: BRONSON
Tornado F-scale: EF2
Property damage: 500.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado spun up two miles northeast of Bronson along 190th Street, around one mile west of the intersection with Emmett Ave, where it ripped a portion of the roof off a single family home and damaged an outbuilding, with debris sent 100 yards to the north into a field.  The tornado continued northeast across open fields until it hit two large metal utility transmission towers, and deposited the electric lines across U.S. Highway 20, resulting in the closure of U.S. Highway 20 east of Lawton for two days. The tornado crossed U.S. Highway 20 less than a mile east of Lawton, then made a more northward turn. As the tornado approached Fayette Avenue, it impacted multiple farmsteads with damage to a few barns and sheds, as well as broken and snapped tree limbs.  A machine shed at one farmstead was completely destroyed along with a concrete silo and lean-to shed. Multiple power poles were snapped along 140th Street. Minor damage was also noted to shingles on a couple single family homes.
The tornado eventually lifted near the intersection of 110th Street and Fayette Avenue.  The average path width was 75 yards and the maximum estimated wind speed was 130 mph. Property damage costs are a rough estimate.

Tornado in BUENA VISTA, IOWA
From 15-DEC-21 17:01:00 to 15-DEC-21 17:06:00 (CST-6)
Location: HANOVER
Tornado F-scale: EF1
Property damage: 200.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This is the third segment of a tornado which developed 2 miles north-northwest of Galva at 1658CST, and tracked northeast through extreme southeast Cherokee County. The tornado entered Buena Vista County at 1701CST, one-half mile south of the intersection of 10th Avenue and 640th Street. Along 640th Street, the tornado destroyed two outbuildings on a farmstead and damaged three others, removed a chimney from the roof of the residence, downed several light poles, and snapped and uprooted several large trees. Numerous other large trees were snapped or uprooted as the tornado tracked northeast over the next two miles, before damaging the roof of a hog confinement along 620th Street between 20th and 30th Avenues. Several houses lost shingles and siding, with occasional tree damage before the tornado lifted one mile southwest of Alta at 1706CST. The tornado was rated EF0 in Ida County, EFU in Cherokee County, and EF1 in Buena Vista County. The average path width in Buena Vista County was 50 yards and the maximum estimated wind speed was 100 mph. Property damage costs are a rough estimate.

Tornado in BUENA VISTA, IOWA
From 15-DEC-21 17:18:00 to 15-DEC-21 17:22:00 (CST-6)
Location: REMBRANDT
Tornado F-scale: EF2
Property damage: 250.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado spun up just north of Rembrandt at 1718CST near the intersection of 120th Avenue and 470th Street. The tornado tracked northeast, and dissipated near the Little Sioux River one mile east of Sioux Rapids at 1722CST.  A residence near the touchdown had siding and roofing torn from the home, along with snapped large pine trees. Along 460th Street just west of U.S. Highway 71, several large wooden power poles were snapped.  The tornado continued northeast, crossing U.S. 71 one-half mile north of 460th Street where it destroyed several small buildings.  More power poles were snapped along 450th Street east of U.S. 71, with the final damage noted in snapped trees along the Little Sioux River east of Sioux Rapids.  The average path width was 75 yards and the maximum estimated wind speed was 115 mph. Property damage costs are a rough estimate.

Tornado in WOODBURY, IOWA
From 15-DEC-21 16:35:00 to 15-DEC-21 16:39:00 (CST-6)
Location: MOVILLE
Tornado F-scale: EF1
Property damage: 200.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado formed around 4 miles east-northeast of Moville, one-quarter mile east of the intersection of Jasper Avenue and 140th Street. The tornado traveled north-northeast for slightly over 4 and one quarter miles before exiting Woodbury County two miles south of Kingsley, just east of the intersection of Knox Avenue and 100th Street.  The tornado continued in Plymouth County for somewhat less than 4 miles before dissipating at 1642CST.  In Woodbury County near the touchdown point, a barn roof was collapsed.  The tornado continued northeast for around a mile and a half before removing most roof panels from another barn. Near the Plymouth County line, the tornado encountered another farmstead which suffered total destruction of a garage and outbuilding. Numerous larger trees were snapped, and debris from damaged buildings was deposited in the trees. The tornado was rated EF1 while in both Woodbury and Plymouth Counties. The average path width in Woodbury County was 50 yards and the maximum estimated wind speed was 110 mph. Property damage costs are a rough estimate.

Tornado in CHEROKEE, IOWA
From 15-DEC-21 17:05:00 to 15-DEC-21 17:08:00 (CST-6)
Location: LARRABEE
Tornado F-scale: EF1
Property damage: 250.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This tornado formed on the southeast fringes of Larrabee, just south of 455th Street. As the tornado crossed 455th Street, it quickly destroyed four silos, a shed and a chicken barn. The tornado traveled northeast over open fields before a few trees were snapped and the east wall of a barn was pulled away along R Avenue just south of 430th Street.  The tornado exited Cherokee County around 4 miles south of Sutherland, one-half mile east of the intersection of Tyler Avenue and 420th Street. The tornado continued in O'Brien County for almost 4 miles before dissipating two miles southeast of Sutherland at 1711CST. The tornado was rated EF1 while in both Cherokee County and O'Brien County. The average path width in Cherokee County was 50 yards and the maximum estimated wind speed was 105 mph. Property damage costs are a rough estimate.

Tornado in CHEROKEE, IOWA
From 15-DEC-21 17:00:00 to 15-DEC-21 17:01:00 (CST-6)
Location: AURELIA
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

This is the second segment of a tornado which developed 2 miles north-northwest of Galva at 1658CST, and entered Cherokee County 4 miles north of Galva just east of Marshal Avenue at 1700CST. The tornado tracked over open farmland in extreme southeast Cherokee County with no damage indicators, before it entered Buena Vista County at 1701CST, where the tornado lifted one mile southwest of Alta at 1706CST. The tornado was rated EF0 in Ida County, EFU in Cherokee County, and EF1 in Buena Vista County. The average path width in Cherokee County was estimated at 50 yards.

Tornado in IDA, IOWA
From 15-DEC-21 16:42:00 to 15-DEC-21 16:51:00 (CST-6)
Location: BATTLE CREEK
Tornado F-scale: EF1
Property damage: 200.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A tornado formed in an open field between 280th and 290th Streets near the Woodbury and Ida County line southwest of Battle Creek.  The tornado tracked northeast for around one mile before it removed shingles from a house southwest of Battle Creek. As the tornado continued northeast, four additional farmsteads were impacted with
several outbuildings damaged or destroyed. Several trees were damaged and a few power poles were snapped north of Battle Creek. The tornado crossed U.S. Highway 59 just north of 190th Street, and lifted approximately 7 miles north of Ida Grove. The average path width was 50 yards and the maximum estimated wind speed was 100 mph. Property damage costs are a rough estimate.

Tornado in IDA, IOWA
From 15-DEC-21 16:58:00 to 15-DEC-21 17:00:00 (CST-6)
Location: GALVA
Tornado F-scale: EF0
Property damage: 75.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado developed 2 miles north-northwest of Galva, one-half mile southwest of the intersection of 120th Street and Landmark Avenue.  The tornado tracked northeast to a farmstead on the northeast corner of the intersection, where a hoop barn was destroyed and the roof partially removed from a residence. The tornado exited Ida County 4 miles north of Galva just east of Marshal Avenue at 1700CST. The tornado clipped the far southeast corner of Cherokee County, then entered Buena Vista County at 1701CST, where the tornado lifted one mile southwest of Alta at 1706CST. The tornado was rated EF0 in Ida County, EFU in Cherokee County, and EF1 in Buena Vista County. The average path width in Ida County was 50 yards and the maximum estimated wind speed was 85 mph. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:23:00 to 15-DEC-21 16:24:00 (CST-6)
Location: (SUX)SIOUX CITY ARPT
Magnitude: 71.00 MG
Reported by: ASOS

A thunderstorm wind gust of 82 mph was measured by Automated Surface Observing System KSUX.

Tornado in BUENA VISTA, IOWA
From 15-DEC-21 17:07:00 to 15-DEC-21 17:12:00 (CST-6)
Location: ALTA
Tornado F-scale: EF1
Property damage: 100.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado which spun up 7 miles south-southwest of Aurelia continued into Buena Vista County at 1707CST near the intersection of 510th Street and 10th Avenue. The tornado continued northeast and lifted one mile south of the Buena Vista County Conservation Park at 1712CST.  Along the track, the tornado caused siding and roof damage to outbuildings near 20th Ave and 490th Street, and removed walls of a machine shed along 480th Street west of 30th Avenue. Numerous wooden power poles were snapped along 470th and 460th Streets. The tornado was rated EF1 in both Cherokee and Buena Vista Counties. The average path width was 75 yards in Buena Vista County and the maximum estimated wind speed was 110 mph. Property damage costs are a rough estimate.

Tornado in DICKINSON, IOWA
From 15-DEC-21 17:39:00 to 15-DEC-21 17:43:00 (CST-6)
Location: FULLER FLD ARPT
Tornado F-scale: EF1
Property damage: 200.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A tornado spun up 3 miles east-northeast of Fostoria one-half mile south of 260th Street east of 250th Avenue.  The tornado tracked north just east of 250th Avenue, and snapped several power poles along 260th and 250th Streets.  Two farms between 250th and 240th Streets were struck by the tornado, which peeled back the roof of an outbuilding and damaged several large trees.  The most significant damage occurred along 235th Street where a portion of the south-facing roof was removed from a house and an outbuilding to the north of the house was destroyed.  The tornado tracked through open fields for another mile before it lifted 2 miles east of Milford. The average path width was 25 yards and the maximum estimated wind speed was 100 mph. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:28:00 to 15-DEC-21 16:29:00 (CST-6)
Location: LAWTON
Magnitude: 70.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds tossed an empty grain bin, and resulted in considerable tree damage. Minor roof damage was also done to the residence at this location. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:31:00 to 15-DEC-21 16:32:00 (CST-6)
Location: LAWTON
Magnitude: 69.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds removed numerous shingles from a house. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:28:00 to 15-DEC-21 16:29:00 (CST-6)
Location: LAWTON
Magnitude: 69.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds dented large grain bins on the southeast facing side, and numerous shingles were removed from the south side of a house. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:41:00 to 15-DEC-21 16:42:00 (CST-6)
Location: KINGSLEY
Magnitude: 72.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds peeled back large sections of north-facing roof on a hog confinement building. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:34:00 to 15-DEC-21 16:35:00 (CST-6)
Location: ANTHON
Magnitude: 74.00 EG
Property damage: 75.00K
Reported by: Public

Thunderstorm winds destroyed a garage and cattle barn. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:21:00 to 15-DEC-21 16:21:00 (CST-6)
Location: SIOUX CITY
Magnitude: 61.00 EG
Reported by: Public

A large tree was uprooted by thunderstorm winds.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:23:00 to 15-DEC-21 16:23:00 (CST-6)
Location: BRONSON
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Roofing material on several hoop barns was damaged. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:25:00 to 15-DEC-21 16:26:00 (CST-6)
Location: SIOUX CITY
Magnitude: 65.00 EG
Property damage: 10.00K
Reported by: Public

Several power poles were leaning after strong thunderstorm winds. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:38:00 to 15-DEC-21 16:39:00 (CST-6)
Location: DANBURY
Magnitude: 64.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A roof was blown off a shed by thunderstorm winds. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:39:00 to 15-DEC-21 16:40:00 (CST-6)
Location: KINGSLEY
Magnitude: 78.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds ripped a porch overhang off the exposed south-facing side of a house, with debris impacting a fence and home north of this location. Property damage costs are a rough estimate.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 16:56:00 to 15-DEC-21 16:57:00 (CST-6)
Location: MERIDEN
Magnitude: 83.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorms winds removed a portion of the roof of a well-built machine shed. Property damage costs are a rough estimate.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 16:56:00 to 15-DEC-21 16:57:00 (CST-6)
Location: MARCUS
Magnitude: 70.00 EG
Property damage: 50.00K
Reported by: Emergency Manager

Thunderstorm winds removed sections of the roof off a few buildings and blew a semi-truck off the road. Property damage costs are a rough estimate.

Thunderstorm Wind in WOODBURY, IOWA
From 15-DEC-21 16:19:00 to 15-DEC-21 16:20:00 (CST-6)
Location: HORNICK
Magnitude: 65.00 EG
Property damage: 25.00K
Reported by: Emergency Manager

Thunderstorm winds overturned several propane tanks. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:39:00 to 15-DEC-21 16:40:00 (CST-6)
Location: KINGSLEY
Magnitude: 72.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

South-facing door of outbuilding was buckled by thunderstorm winds, which resulted in failure of the east wall of the building. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:40:00 to 15-DEC-21 16:41:00 (CST-6)
Location: KINGSLEY
Magnitude: 82.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds destroyed two farm outbuildings and flipped a truck on its side. Property damage costs are a rough estimate.

Thunderstorm Wind in PLYMOUTH, IOWA
From 15-DEC-21 16:40:00 to 15-DEC-21 16:41:00 (CST-6)
Location: KINGSLEY
Magnitude: 83.00 EG
Property damage: 35.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorms winds caused failure of a south-facing door which resulted in uplift of numerous roof panels and removal of insulation.  Debris was deposited to the north and northwest of the building amongst several large trees which were snapped. Property damage costs are a rough estimate.

Thunderstorm Wind in DICKINSON, IOWA
From 15-DEC-21 17:35:00 to 15-DEC-21 17:36:00 (CST-6)
Location: WEST OKOBOJI
Magnitude: 52.00 EG
Reported by: Emergency Manager

Several tree limbs were broken by thunderstorm winds.

Tornado in CHEROKEE, IOWA
From 15-DEC-21 16:59:00 to 15-DEC-21 17:07:00 (CST-6)
Location: AURELIA
Tornado F-scale: EF1
Property damage: 1.00M
Crop damage: 0.00K
Reported by: NWS Storm Survey

The tornado spun up 7 miles south-southwest of Aurelia just west of the intersection of T Avenue and 610th Street. The tornado moved either northeast or north-northeast along its track and exited Cherokee County at 1707CST near the intersection of 510th Street and 10th Avenue. The tornado continued northeast and lifted one mile south of the Buena Vista County Conservation Park at 1712CST.
Shortly after touchdown, the tornado partially collapsed the roof on a hog confinement which killed 13 hogs. Debris from this building was strewn for one to two miles to the northeast.  On a northeastward track, another animal confinement farm was struck by the tornado after a couple minutes which resulted in loss of several roof panels on multiple buildings. At this point the tornado shifted path toward more of a north-northeast direction and moved into Aurelia.  A drying unit was removed from the top of a grain elevator on the south edge of town.  Most of the damage throughout the eastern half of Aurelia was snapped trees, which caused collateral damage to numerous roofs and windows along the path. The tornado moved through the golf course snapping and uprooting numerous trees. The tornado continued with a shift to a more northeast track, and destroyed a barn and three outbuildings along 535th Street northeast of Aurelia. Additional damage occurred to a machine shed and large trees along the Cherokee and Buena Vista County line. The tornado was rated EF1 in both Cherokee and Buena Vista Counties. The average path width was 150 yards in Cherokee County and the maximum estimated wind speed was 110 mph. Property damage costs are a rough estimate.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:25:00 to 15-DEC-21 17:25:00 (CST-6)
Location: ROYAL
Magnitude: 65.00 EG
Reported by: Emergency Manager

Thunderstorm winds downed a large pine tree.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:30:00 to 15-DEC-21 17:32:00 (CST-6)
Location: SPENCER
Magnitude: 70.00 EG
Reported by: Emergency Manager

Numerous large trees were downed by thunderstorm winds in Spencer.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:24:00 to 15-DEC-21 17:25:00 (CST-6)
Location: MACLAY
Magnitude: 64.00 EG
Reported by: Emergency Manager

Thunderstorm winds snapped and uprooted several trees and tipped over a trailer.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:14:00 to 15-DEC-21 17:15:00 (CST-6)
Location: PETERSON
Magnitude: 56.00 EG
Reported by: NWS Storm Survey

Thunderstorm winds downed several large tree limbs.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 17:02:00 to 15-DEC-21 17:03:00 (CST-6)
Location: AURELIA
Magnitude: 78.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Thunderstorm winds blew in the south facing doors of a metal shed, which caused complete removal of the roof. Property damage costs are a rough estimate.

Thunderstorm Wind in CHEROKEE, IOWA
From 15-DEC-21 17:02:00 to 15-DEC-21 17:03:00 (CST-6)
Location: AURELIA
Magnitude: 87.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A half-dozen power poles were snapped off at the ground by thunderstorm winds. Property damage costs are a rough estimate.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:14:00 to 15-DEC-21 17:15:00 (CST-6)
Location: PETERSON
Magnitude: 76.00 EG
Reported by: NWS Storm Survey

Thunderstorm winds snapped a large pine tree.

Thunderstorm Wind in CLAY, IOWA
From 15-DEC-21 17:14:00 to 15-DEC-21 17:15:00 (CST-6)
Location: PETERSON
Magnitude: 65.00 EG
Reported by: Emergency Manager

Large tree limbs were downed by thunderstorm winds.

Thunderstorm Wind in O'BRIEN, IOWA
From 15-DEC-21 17:12:00 to 15-DEC-21 17:13:00 (CST-6)
Location: SUTHERLAND
Magnitude: 61.00 EG
Reported by: NWS Storm Survey

Thunderstorm winds downed severe large diameter tree limbs.

Thunderstorm Wind in BUENA VISTA, IOWA
From 15-DEC-21 17:07:00 to 15-DEC-21 17:08:00 (CST-6)
Location: STORM LAKE ARPT
Magnitude: 56.00 EG
Reported by: NWS Storm Survey

Thunderstorm winds downed several large tree branches.