A 5-ton tractor remained missing after nine tornadoes left a trail of damage across southeast Montana and northwest South Dakota on Thursday, according to newly released results of a damage survey by the National Weather Service.
The initial results of the survey were published Monday. Analysis of the data and observations is still ongoing, but the weather service said reports indicate there were five tornadoes in Harding County, S.D., and four in Carter County, Mont.
The first Harding County tornado crossed the Montana-South Dakota state line near Forty-eight Mile Creek at 8:20 p.m., approximately 10 miles south-southwest of Camp Crook, based on video evidence and eyewitness reports. It traveled northeastward, crossing South Camp Crook Road before dissipating near Sagebrush Draw at 8:30 p.m.
West of South Camp Crook Road, the first tornado debarked some trees, caused the collapse of some exterior walls of a home, and destroyed some outbuildings. Based on this damage, winds were estimated at 136 mph.
The tornado also lofted and destroyed some farm machinery, including a 5-ton tractor that has yet to be found.
As the tornado crossed Camp Crook Road, several hundred yards of fence were either flattened or littered with debris, and widespread sagebrush destruction was observed.
East of Camp Crook Road near Hawk Creek, a large farm outbuilding was destroyed, and its foundation was ripped from the ground and broken apart. A tractor tire found on this property may have been part of the tractor lost approximately 2 miles to the southwest.
While much of the damage was consistent with an EF-1 or EF-2 tornado, the most significant damage was consistent with an EF-3 tornado. The rankings on the Enhanced Fujita scale of tornado severity go up to EF-5.
The next three Harding County tornadoes occurred over mainly rural areas, southeast of Camp Crook and southwest of Buffalo. The National Weather Service is not aware of any damage associated with those tornadoes yet, so the strengths of the tornadoes is unknown.
The county's final tornado developed just south of S.D. Highway 20 near mile marker 17 around 9:10 p.m, where it snapped power poles and trees near a residence. A farm outbuilding was also severely damaged, with collapse of most exterior walls.
Based on video evidence, the tornado then continued northward across rural areas northwest of Buffalo and crossed Clanton Road before dissipating at 9:26 p.m.
The National Weather Service said it planned to survey tornado damage southeast of Sundance and the Spearfish Canyon area Tuesday.
Meanwhile, damage reports continue to surface not only from Thursday's tornadoes but also from other violent weather that occurred Thursday and Friday.
Two people were treated at the Regional Health Sturgis Hospital Emergency Department on Friday with storm-related injuries, according to a Regional Health spokesman. No further information about the injured people was immediately available.
The Black Hills National Forest is assessing impacts of a Friday night storm in the Bearlodge and Northern Hills districts. The storm’s path traveled through the Cement Ridge area of the Bearlodge District and headed east toward Spearfish Canyon.
Crews worked over the weekend to open most of the main roads in the forest, but some interior roads remain blocked by fallen trees.
Hiking trails and motorized use trails are being assessed this week.
“We urge visitors to avoid these areas to allow crews to complete the needed work and allow employees to work in a safe environment,” said Mike Gosse, Bearlodge District ranger. “We also encourage visitors to be vigilant while recreating on the forest over the busy Independence Day holiday for any trees that may be leaning or weakened from the storm.”
A reconnaissance flight was planned Monday afternoon to map the storm’s path and get an aerial overview of the damage.