All Weather News

20 Year Anniversary of South Dakota’s Most Destructive Tornado

31 May 2018, 10:56 am

On May 30th 1998, a violent tornado caused widespread damage in Spencer, South Dakota. National Weather Service survey teams were sent out days after the tornado to survey the damage left behind. The survey teams indicated a multiple vortex tornado touched down in Spencer, and two other tornadoes touching down west of Spencer. The storm is still recorded as South Dakota’s most destructive and second deadliest tornado.

[Radar loop of Spencer tornado from 1998. Note:  The Green “Home” location on the above image denotes Spencer, SD.]

Spencer is in extreme western McCook County, about 45 miles west-northwest of Sioux Falls, SD. The tornado killed six people, injured more than one-third of the town’s 320 residents, and destroyed most of the town’s 190 buildings. Damage was estimated at $18 million. The Spencer tornado (rated F4 on the Fujita Tornado Intensity Scale) was one of five tornadoes, along a nearly continuous damage track approximately 30 miles long. All five tornadoes were produced by one supercell thunderstorm during a 1 hour and 5-minute period. The most devastating damage was limited to less than 1 mile along the tornado track, but significant damage (F1 to F3 intensity) was inflicted on several farmsteads in McCook County and neighboring Hanson County, including damaged or destroyed buildings, loss of crops, and loss of approximately 75 head of livestock.

The first tornado touched down around 8:15 p.m. CDT, producing a storm path that began about 4 miles northwest of Fulton and ended near Fulton. A second damage path was observed about two miles north of Fulton extending five miles southeast and ending two miles northwest of Farmer.

The multiple vortex tornado that hit Spencer, originated near Long Lake in Hanson County. The storm intensified as it moved into Spencer at approximately 8:44pm CDT, as two storm cells merged into one. Wind speeds were estimated at upwards of 200 mph, which resulted in devastating damage in Spencer where nearly all structures were damaged or destroyed beyond repair.

[Photo take 4.5 miles east of Spencer looking west. Photos courtesy of Chris Lenz, via National Weather Service in Sioux Falls]

[Damage in Spencer, SD. From Steve Marks Assistant Coordinator Greensboro-Guilford County Emergency Management]

You can read the National Weather Service full report on the tornado at this link.

For WeatherNation: Meteorologist Mace Michaels