Common Terms Used When Describing Tropical Events

Posted: June 9, 2023 9:30 am

With the official start of the 2023 Atlantic hurricane season now underway, this is a good time to review some basic hurricane terms that may come in handy as you gather information about storms headed your way.

Here are some of the most common terms that meteorologists will use when discussing hurricane forecasts.

Central Pressure

All major types of tropical features, including depressions, storms, and hurricanes, are all defined by their low pressure system. The air pressure located in the center of the storm system is used to discern how powerful the feature is in addition to its maximum sustained winds.

In general terms, a stronger and more dangerous storm is associated with a lower central pressure reading.

For instance, the central pressure within the deadly Hurricane Katrina hit 26.64 inches of mercury, the equivalent of 902 millibars. The record low pressure reading belongs to Typhoon Tip, hitting 25.69 inches of mercury, or 870 millibars, dating back to October of 1979.

Eye

Most everyone is familiar with the eye of a hurricane. This central part of a tropical feature is a defining characteristic of a named storm. The eye is most noticeable as the storm grows in size and intensity. The irony is that the winds are calm in the center of the eye. Skies are also typically clear in the eye.

According to the National Oceanic and Atmospheric Administration (NOAA), this part of the storm can vary in size with most measurements coming in at 20 to 40 miles across.

One of the largest eyes on record happened in 1960 when the center of Typhoon Carmen grew to over 200 miles across while it churned in the western Pacific Ocean.

However, even strong hurricanes can feature small eyes. These types of eyes are called pinhole eyes.

Eyewall

The eyewall is located directly outside of the wall. This is known as the most powerful part of the hurricane, featuring the strongest wind speeds. This is also the part of the storm that is most likely to see lightning.

Last year’s Hurricane Ian demonstrated its growing intensity through its frequent lightning strikes as it inched closer to the Florida peninsula before making a direct strike on the Fort Myers area.

Spiral or Outer Bands

The moisture associated with a tropical storm or hurricane can expand hundreds of miles from the eye. These spiral bands are often referred to as the outer bands of the storm. The rain rotates around the eye of the storm forming a spiral shape.

The outer bands of large storms can impact land days before the hurricane makes its official landfall. This is also the part of the storm where you are most likely to see tornadic activity because of the different atmospheric elements present in the bands.

Left Front Quadrant

Every tropical storm and hurricane is also defined by its four distinct quadrants. The National Hurricane Center (NHC) uses these quadrants to track the storm. The left front quadrant is located to the left of the storm’s track through the water, leading in the direction that the storm is moving.

Wind flow in the left front quadrant comes in at northeast to southwest. This quadrant boasts a lower threat of both storm surge and tornadoes, making it less impactful than the strongest quadrant.

Right Front Quadrant

Conversely, the strongest part of a hurricane is usually found in the right front quadrant. You can expect the winds to blow in the same general direction that the feature is moving, generating higher wind speeds and a greater amount of potentially dangerous storm surge.

There are also more tornadoes that form in this part of the hurricane.

The impact zone of the right front quadrant is typically where you would find the highest amount of damage and loss of life. The recent Hurricane Ian was a prime example of this. The right front quadrant came on shore in Fort Myers, Florida.

Not surprisingly, Fort Myers Beach and the surrounding area saw the most significant destruction. However, the Tampa and Sarasota areas were largely spared because they were hit with the left front quadrant.

Right Rear Quadrant

With winds blowing from the southwest to the northeast, it is not surprising to learn that the right rear quadrant is best known for its flooding and storm surge concerns.

These concerns are heightened in areas that were slammed by the right front quadrant just prior to the corresponding rear quadrant moving through the already vulnerable area.

Lastly, this is also a common spot for tornadoes to spin up.

Left Rear Quadrant

The left rear quadrant is most widely known as the weakest area of a hurricane. That said, you cannot relax just because your area will be taking the brunt from this section of the storm. There is always the threat of flooding, damaging winds, and more in the path of the left rear quadrant.

Storm Surge

One last thing to familiarize yourself with is the concept of storm surge. This can often be one of the most damaging and deadliest features of any tropical event, even more so than the wind and torrential rain.

The highest amount of storm surge is usually located at the leading edge of the storm and in the right front quadrant.

You do not need to be in the path of a hurricane or a tropical storm to see a destructive storm surge. Many nor’easters or other severe coastal storms also unleash storm surge that should be taken seriously.

Did you find this content useful? Feel free to bookmark or to post to your timeline for reference later.

Recent Posts