A complex line of severe storms started in Nebraska and raced northeast between speeds of 50 to 70mph. These strong storms brought powerful widespread damaging straight-line winds to a good part of eastern, South Dakota on Thursday. This event is known as a derecho, a line of long-lived thunderstorms that brings at least 60mph wind gusts and travels over 400 miles.
Within this line of wind, several tornadoes had developed, one causing significant damage to the city of Castlewood.
Photo Credit: National Weather Service
Preliminary reports from the National Weather Service estimated peak wind speeds of 120mph as the tornado traveled just under two miles. The weather service gave the tornado an EF2 rating.
Several homes and Castlewood school were severely damaged during the event and debris from buildings could be found miles north of the town.
Luckily nobody was killed during the event, but one person did receive minor injuries and was taken to the hospital.
An even stronger tornado dropped down near the town of Gary in northeast, South Dakota. The National Weather Service reported that this tornado was an EF2 with peak winds of 135mph.
Photo Credit: National Weather Service
This tornado was on the ground for a very short period, traveling just under half of a mile. One person was injured in this tornado.
A tornado about four miles north of Lake Kampeska removed a garage from a home with additional damage done to the home's roof. Debris from the home could be found about a half-mile away as peak winds from the tornado reached 110mph. This tornado was rated an EF1 and was only on the ground for less than a quarter of a mile. No injuries were reported.
Photo Credit: National Weather Service
Two other EF1 tornadoes were recorded, with one just east of Tunerville in Deuel County and the other about seven miles south of Webster.
With peak winds of 100mph, a tornado near Tunerville damaged a hunting lodge and uprooted trees. The tornado continued northward heading for a family home. The family at the time was inside their camper before the storm hit. The family then received a weather alert about the pending danger and went into a sturdier shelter. The camper was picked up by the tornado and dropped on the home. The family was unharmed from the event.
Photo Credit: National Weather Service
The last tornado reported occurred in Day County, south of Webster. This twister was on the ground for just about a minute but still damaged an outbuilding by pulling the roof off and blowing out an interior wall. The estimated peak winds in this twister were 100mph.
Photo Credit: National Weather Service