Biography of the Storm
On 30 May 1998, the deadliest and most destructive tornado in South Dakota history --
and the most intensely observed and analyzed -- struck Spencer SD.
At approximately 8:40 p.m. (all times Central Daylight Time [CDT]) on Saturday, May 30,
1998, a violent tornado struck the small town of Spencer, South Dakota. Spencer is in
extreme western McCook County, about 45 miles west-northwest of Sioux Falls. 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 is 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
Take a Chronological
Look at the weather events that lead up to the tornado that devastated Spencer.
Wurman, a storm chaser that studied and witnessed the storm.
overview, complete with photographs from Roger Edwards of the Storm Prediction Center.
Firsthand accounts of the tornado by teams of storm
chasers positioned around the town of Spencer.
Doswell - National Severe Storms Laboratory
- Positioned 3 miles west of Spencer
- Texas Severe Storms Assoc.
Al Moller -
National Weather Service, Ft. Worth, TX
- Agoura Hills, California
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