Spencer tornado
The 1998 Spencer tornado was a large and destructive tornado that tore through communities along Hanson and McCook Counties, in the southeastern part of South Dakota on May 30, 1998. It particularly devastated the small city of Spencer, and was part of the a historic late-May tornado outbreak and derecho that swept across the northern United States and southern Canada. In South Dakota, the storm was the deadliest tornado to occur in the state, and was the fifth deadliest of the 1998 season.
What was the Spencer tornado?
The Spencer tornado was a large and destructive F4 tornado that struck South Dakota on May 30, 1998. It formed as part of a historic late-May tornado outbreak that swept across the northern United States and southern Canada. The storm tore through communities in Hanson and McCook Counties, particularly devastating the city of Spencer. It represents the deadliest tornado to occur in South Dakota history. Survey results from the National Weather Service officially classified the event as an F4 on the Fujita Scale.
What was the Spencer tornado wind speed?
The Spencer tornado produced wind speeds ranging from 207 to 260 mph according to National Weather Service damage surveys. Mobile radar measurements from a Doppler on Wheels truck recorded instantaneous wind gusts of up to 264 mph. While the tornado moved through the town, the radar measured 5-second average winds exceeding 225 mph. These high velocities placed the tornado firmly in the F4 range of the Fujita Scale. The measurements were taken from 20 to 40 meters above ground level.
What was the Spencer tornado path?
The Spencer tornado formed over rural Hanson County northwest of Farmer at 8:26 p.m. CDT. It tracked southeast across rural farmland for several minutes before crossing into McCook County to strike the town of Spencer. The storm maintained a destruction path approximately 14 miles long and nearly 1 mile wide through the town. It finally dissipated around 5 miles southeast of Spencer just before reaching Interstate 90. The total duration of the tornado lasted 26 minutes.
How many people died in the Spencer tornado?
The Spencer tornado claimed the lives of 6 residents. This event marked the first tornado in South Dakota to cause fatalities since 1970. In addition to the deaths, 41 individuals required hospitalization due to injuries sustained during the storm. Five of the six fatalities occurred inside an apartment complex that experienced the most violent wind speeds. The tornado caused no additional documented injuries beyond the 41 hospitalized victims.
What did the Spencer tornado destroy?
The tornado leveled nearly all 190 homes and structures located in Spencer. Specific buildings destroyed include the town water tower, the bank, five churches, the post office, the fire department, and the nursing home. It also destroyed numerous grain bins and local business structures throughout the community. Violent winds threw vehicles and leveled well-constructed homes while stripping others of their foundations. A receipt from the town was later discovered 80 miles east of Spencer near Chandler.
What caused the Spencer tornado?
The Spencer tornado resulted from a severe weather setup involving a strong approaching jet stream and a departing jet stream creating low pressure over the Missouri River. Meteorological conditions included high moisture, strong wind shear, and CAPE values reaching 4050 J/kg. A dryline and cold front triggered the formation of isolated supercells by 6:00 p.m. CDT. One of these supercells produced five tornadoes in succession as it moved across Hanson and McCook Counties. The Storm Prediction Center had issued a Moderate Risk for the region.
What happened after the Spencer tornado?
Emergency services responded to the disaster immediately following the destruction. Former FEMA Director James Lee Witt coordinated with state officials including Bill Janklow and Rick Weiland to provide food and shelter to survivors. Following the storm, the population of Spencer dropped from 315 to 145 residents. Most property owners faced difficult decisions, with 156 remaining undecided about rebuilding their homes. The event resulted in $18.5 million in total damages, standing as the costliest tornado in South Dakota history.
Spencer Tornado Track
The mapped ground track below shows the surveyed touchdown point, damage corridor, and dissipation coordinates recorded by NWS field crews. The Spencer tornado traveled 14 miles across Hanson County, McCook County, South Dakota. Coordinates are derived from the official SPC historical tornado database.
How many people died in the Spencer tornado?
The Spencer tornado caused 6 fatalities.
What was the Fujita scale rating of the Spencer tornado?
The National Weather Service officially classified the Spencer tornado as an F4.
How much damage did the Spencer tornado cause?
The Spencer tornado caused $18.5 million in total damages, which is the highest amount in South Dakota history.
Did the Spencer tornado happen at night?
Yes, the tornado formed at 8:26 p.m. CDT and impacted the town of Spencer between 8:38 p.m. and 8:45 p.m. CDT.