Monday, Curtis Harmon of Morganton, N.C., walked through his family’s heavily wooded and hilly property off of Tester Road in Butler.
Harmon stepped over fallen branches as he pointed out the damage left over after a sever thunderstorm swept through the region Friday.
“Look, you can see where trees are twisted,” Harmon said. “I have never seen straight-line winds do that.”
Harmon and his family, like many in the area, believes that the damage on their property in Butler, which is located right on the Watauga River and is used as a campground, was caused by a tornado.
“I am one hundred percent sure it was a tornado,” Harmon said. “There ain’t not doubt in my mind. There is no way that was caused by straight-wind damage.”
Friday evening, like they do every year, Harmon and 28 members of his family were camping on their property. Harmon had left before the storm hit that evening, but said many of his family members were still there and had to race for shelter.
“They said it happened so fast that they couldn’t get to shelter hardly,” Harmon said.
Harmon said that, Danny Harmon, who neighbor’s the camping area, said he saw from his front porch what looked like a funnel cloud go over the area where Harmon and his family were camping.
Ever since Friday, the National Weather Service – Morristown, which monitors weather in the East Tennessee region, have been receiving calls from people wanting to know what happened Friday night.
Meteorologist Sam Roberts with NWS said that they are confident that the storm that rampaged through the region Friday evening did not produce tornadoes. According to Roberts, most of the damage was caused by straight-line winds and down bursts.
There are two things that makes Roberts and his colleagues certain that a tornado did not touched down in the area they monitor.
First off, after reviewing radar data from Friday evening, Roberts said there are no indications of tornadic activity.
“We went back and looked and saw no signs of rotation at all on the radar,” Roberts said. “It was classic down burst winds and straight-line wind damage. Looking at radar estimates, the winds were probably around 80 mph. Give or take a little bit.
“The thing is, with 80 mph winds, if you look at the EF scale, you start getting into the EF 0 range of tornados,” Roberts added. “The wind speeds that occurred were in line with a weak tornado, even though a tornado didn’t occur. 80 mph winds can do a lot of damage.”
Secondly, Roberts said that photos of the damage are in line with the straight-line winds and down burst scenarios, and that most of the time it easy to tell the difference between photos of damage caused by straight-lined winds and tornadoes.
“Typically, with straight-line wind damage you have everything laid over in a single unit of direction,” Roberts said. “If the storm is moving from east to west, then everything will be laying down in a easterly direction. Generally, in the same direction.”
As Harmon walked around his family’s property Monday, he pointed out how not all of the trees had fallen in the same direction, especially in the path of destruction that had cut through the woods, leaving mangled and twisted trees laying on the ground .However, Roberts said that when dealing with certain terrains, like seen at the Harmon’s property, it can get trickier to discern which way a tree has been blown.
“What can make it tricky sometimes is if you have terrain involved that has any kind of slope, “ Roberts said. “Lets say that you have a storm moving towards the east, but a storm starts going up slope, then just due to gravity, the trees are going to fall in direction against what they should have. They are going to back towards the west. ”
Roberts said that when looking at trees that were in the path of a tornado, the trees will not point in the same direction and will have a convergence pattern, causing them to point towards the middle of the damage. Roberts also noted like straight-line wind damage, tornado damage patterns can become confused when certain terrains are involved. Roberts also said that people can confuse straight-lined wind damage with tornado damage due to trees being snapped off half way up, noting that both weather events can cause trees to break in half.
After looking over the info the weather service has, Roberts and his colleagues are certain that a tornado did not occur Friday.
“After looking back at the radar, we are confident,” Roberts said. “We are a hundred percent sure.”