Twenty-one vehicles were involved in the crash, and Montana Highway Patrol Sgt. Jay Nelson said authorities believe the weather was a factor. “It looks like there were strong winds, causing a dust storm with zero visibility,” he said. While the highway patrol did not have an immediate count of the number of injuries, Nelson said additional ambulances had to be called from Billings to assist. Gov. Greg Gianforte said on Twitter: “I am deeply saddened by the news of a mass tragedy near Hardin. Please join me in prayer to lift up the victims and their loved ones. We are grateful to our first responders for their service.” Montana Attorney General Austin Knudsen, who oversees the highway patrol, said in a statement: “The Montana Highway Patrol is on scene with other first responders investigating the incident. We will release more information as it becomes available and appropriate out of respect for the lives lost and their loved ones. “My prayers are with everyone affected by the tragic events during the dust storm in Big Horn County today,” Knudsen added. The incident occurred 3 miles (5 kilometers) west of Hardin. A video from The Billings Gazette showed hundreds of tractor-trailers, RVs and cars backed up for miles along the interstate’s two eastbound lanes. The dust storm’s roots can be traced back several hours, when storms appeared in central southern Montana between 1 and 2 p.m. and slowly began to move eastward, according to Nick Vertz, a meteorologist with the National Weather Service in Billings. Those storms produced a powerful storm that blanketed Hardin and other parts of Montana from mid-afternoon to 9 pm Friday. Forecasters predicted the possibility of isolated hail the size of a quarter, scattered wind gusts of up to 75 mph (121 km/h) and frequent lightning. A so-called “outflow” — or a wave of wind produced by the storms but can travel faster than them — flew east/southeast about 30 miles (48 kilometers) ahead of the storms, Vertz said. A wind gust of 40 mph (64 km/h) was recorded at the nearby Big Horn County Airport at 4:15 p.m. By the next reading of the airport weather station at 4:35 p.m., gusts had reached 62 mph (100 km/h). Another reading 20 minutes later recorded a gust of 64 mph (103 km/h). The wind easily whipped up the dust — a product of recent temperatures in the 90s and triple digits last week — and reduced visibility to less than 1/4 mile (0.4 km). “If they were looking up at the sky while they were in Hardin, they probably didn’t see much of what you would think of a storm cloud, maybe not much at all,” Vertz said. “It was just a wind wave that kind of came out of nowhere.” As first responders try to clear the debris, the meteorologist said they can expect to be safe from additional winds and storm surge. “It should be a relatively clear, calm night for them,” he said.
