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 of livestock.

Take a Chronological Look at the weather events that lead up to the tornado that devastated Spencer.

Meet Joshua Wurman, a storm chaser that studied and witnessed the storm.

An excellent 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.
Chuck Doswell - National Severe Storms Laboratory
Roger Edwards - Positioned 3 miles west of Spencer
Martin Lisius - Texas Severe Storms Assoc.
Al Moller - National Weather Service, Ft. Worth, TX
William Reid - Agoura Hills, California

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