NASHVILLE, Tenn. (WKRN) — Tropical cyclones can be intimidating enough on their own, but when you add in the threat of tornadoes, they can be downright scary.
Why do tropical cyclones bring a tornado threat?
Well, it all has to do with the one of the key ingredients of tornado formation called wind shear.
We’ve talked about this in past Weather Authority University segments. Wind shear is the difference between the wind speed and direction in different levels of the atmosphere.
That wind shear will help to create the rotating column of air that eventually stretches to the ground to become a tornado.
Believe it or not, tropical cyclones don’t like wind shear because wind shear weakens it.
Wind shear isn’t a tropical cyclone ingredient when the storm is out over open water. But, it does become an issue when the storm reaches land.
The northeast quadrant of the storm generally hits the land first.
That interaction creates friction, and that friction drives wind shear.
Therefore, it’s in that northeast quadrant of a tropical cyclone where you’ll find the most likely tornado threat.
We saw examples of that with Hurricane Ida just this past week.