Breaking News
More () »

What is wind shear and why does it inhibit hurricanes?

A new disturbance in the Atlantic has a low chance of development.

ST. PETERSBURG, Fla. — Earlier today, the 10 Tampa Bay Weather Team was tracking a new tropical wave in the tropical Atlantic. 

The area of stormy weather was only given a 10 percent chance of further development, partly because of the wind shear in the area.

Wind shear can make or break a tropical storm or hurricane.

What is it? 

Simply a change in wind speed or direction, typically as you go up into the atmosphere. This is known as vertical wind shear. 

Strong wind shear usually occurs when the jet stream extends over tropical waters and creates a zone of rapidly increasing wind speed as you go up into the atmosphere.

Credit: 10 Tampa Bay

When a tropical system encounters strong vertical wind shear, the top of the tropical storm or hurricane can be blown hundreds of miles downstream. 

This can cause the storm to become lopsided, pull in drier air and eventually weaken dramatically.

There’s also horizontal wind shear. 

Horizontal wind shear is the change in direction or speed of winds over the surface of the ocean. When a storm encounters strong horizontal wind shear, the storm can be pushed into another direction or even ripped apart by the strong winds. This is most typically experienced when a strong cold front is encountered.

There are occasional cases where a little wind shear causes a tropical cyclone to strengthen. 

Low-to-moderate wind shear can push a tropical cyclone into warmer waters, which are more favorable for development. 

It’s even possible that low to moderate wind shear blowing from the same direction as the rotation of the storm could cause the storm to spin faster and strengthen.

As you track storms this hurricane season with 10 Tampa Bay, remember this general rule of thumb. 

The shear typically must be 20 knots or less for intensification to occur. 

Most instances of rapid intensification of hurricanes occur when the wind shear is 10 knots or less. 

However, large hurricanes can handle shear values as high as 40 knots.

What other people are reading right now:


Download on the App StoreGet it on Google Play

Stay In the Know! Sign up now for the Brightside Blend Newsletter

Paid Advertisement