Special Report: Tornado or Straight Line Winds?

Just over a month ago, Northern Michigan was hit by several waves of severe storms strong enough to knock out power to tens of thousands of people.

It left a lot of you saying it was a tornado.

So we decided to show you what things look like from the ground and high above, explaining the difference between tornado and straight line wind damage.

Back in August, the sounds of chainsaws and chippers were common for so many areas. They’ve been around for weeks in Lakewood on the Green, west of Cadillac

Damage to houses, cars, and the golf course was excessive. A lot of people thought it was a tornado!

So we asked Jeff Lutz from the National Weather Service what the survey team looks for when they evaluate storm damage.

He said they look for the start point, and from there they try to see what kind of direction the trees are. If they are all in the same direction, that is one piece of the puzzle and that is usually means we are in a straight line wind, sometimes a tornado can do that, but not typically.

Looking at the damage from the ground posed a problem. In some spots you couldn’t see around trees. There was just too much debris! 

The good news is we have a drone, so getting above the mess was easy. The drone shows everything is in one direction and there is a fanning out of some of the trees.

Lutz was on the team that looked over this area and determined it was caused by straight line winds, not a tornado.

We headed over to Dighton Road to look at other storm damage. The corn field showed signs of straight line damage as well as a spot just down the roads that was once heavily wooded.

Straight line damage is caused by a microburst, where high winds in a small area rush down to the ground, taking down trees and throwing loose objects around. There was a lot of that around the region but how about tornado damage?

Six tornadoes touched down across the state that day. We went to the one that hit northeast of Alba in Antrim County.

Lutz says they noticed the damage from the road, but things were really obvious when then went around the corner of the house. They could see trees crisscrossing the area, a pattern indicating convergence which is what a tornado usually leaves behind.

This event was a major one for many areas, the good news is it doesn’t happen that often.

Since 1955 there have been more than 1,000 reports of severe thunderstorm wind gusts in June, July and August, the most active time of year for Northern Michigan.

But the severe weather doesn’t end on August 31. In fact, there have been 57 reports of strong gusts in the month of October since 1955.

Tornadoes, on the other hand, happen less often.

Tornadoes in Northern Michigan are most likely to occur in the middle of the summer, though outbreaks later in the fall have occurred.

One notable outbreak was in October 2007. There were 22 reports of strong gusts and four reported tornadoes in Cheboygan, Kalkaska, and Oscoda counties from severe weather.

It goes to show, Northern Michigan is capable of experiencing damaging storms at nearly any time of the year, whether coming from straight line winds or tornadoes!