Hurricanes are some of nature’s strongest storms. They are formed from warm ocean water that gets pushed upwards into cooler air above the surface.
This causes the water to rotate around itself, creating strong winds. But just how fast does a hurricane? We took a closer look at all you need to know.
What Is A Hurricane?
So, just what is a hurricane? A hurricane is referred to as an intense tropical cyclone and is one of the most destructive weather phenomena on Earth.
It is a rotating storm system with sustained wind speeds of 74 mph or higher.
The National Oceanic and Atmospheric Administration (NOAA) defines hurricanes as “tropical cyclones with maximum sustained surface winds of 74 miles per hour or more.”
Hurricanes can be classified by their intensity level:
- Category 1 – Winds between 111-129 mph
- Category 2 – Winds between 130-156 mph
- Category 3 – Winds between 157-177 mph
- Category 4 – Winds between 178-208 mph
- Category 5 – Winds greater than 209 mph
Hurricanes form when warm sea water rises up through the troposphere and cools off in the upper atmosphere.
As it rotates, the water heats up again and becomes even warmer. This creates a large circular area of high pressure which pushes the surrounding air downwards.
When this happens, the air rushes toward the center of the circle, causing the air to rise. This rising air then meets the descending air near the surface, forming a vortex.
Once the air reaches the top of the vortex, it begins to spin clockwise. This rotation continues until the air has reached its highest point.
At this point, the air descends back down to the surface where it forms clouds. These clouds eventually become raindrops that fall back down to the ground.
The process of forming a hurricane takes about 24 hours. During this time, the storm will continue to grow stronger and stronger.
Eventually, the storm will reach its peak strength and begin to weaken.
Why Are Hurricanes So Destructive?
Hurricanes have been known to cause massive damage for centuries.
In fact, they were responsible for killing thousands of people during the 17th century, largely due to a lack of knowledge, understanding, and ability to prepare for the events.
Today, hurricanes still pose a threat to life and property, but modern technology has made it possible to predict these powerful storms before they strike land.
The reason why hurricanes are so dangerous is that they contain very high amounts of energy.
According to NOAA, a Category 5 hurricane contains approximately 10 times the amount of energy as a nuclear bomb.
This means that a single hurricane could destroy millions of homes and kill hundreds of thousands of people.
Hurricanes become stronger as they move toward land. When a hurricane reaches land, it picks up speed. This speeds up the rotation of the hurricane.
It also causes the eye wall to expand. This expansion causes the hurricane to intensify even further.
How Long Can A Hurricane Last?
A hurricane can last anywhere from three days to two weeks. Most hurricanes last longer than seven days.
Some experts believe that a hurricane may last for months if not years.
As mentioned above, a hurricane can change in intensity levels. There are many factors that contribute to this change including:
When a hurricane makes landfall, it causes strong winds to blow across the ocean. However, the direction of the wind does not remain constant.
Instead, it constantly changes. This is called wind shear. If the wind blows from different directions at the same time, it can cause the hurricane to lose power.
When a hurricane first forms, it is usually cold. As the hurricane gets closer to the coast, the air temperature increases.
The higher air temperature causes more moisture to evaporate into the air. This leads to an increase in cloud formation.
Sea Surface Temperatures
If the sea surface temperature is too low, there won’t be enough heat to create clouds. This results in less rainfall.
On the other hand, if the sea surface temperature is extremely hot, the air will hold onto more moisture. This leads to increased precipitation.
Water Vapor Content
If the air is dry, it cannot hold on to much moisture. This means that the clouds will not produce any rain.
If the air is humid, however, it can hold on to more moisture. This allows the clouds to release their moisture into the air.
When a hurricane makes contact with the ocean, it creates a large pressure difference between the water and the air.
This causes the air to rise up. As the air rises, it cools off. This causes the air pressure to decrease.
During a hurricane, the ocean waves crash against the shoreline. These crashing waves cause a huge amount of force to build up.
This force is released when the wave hits the beach. This is called storm surge. Storm surges can reach heights of over 20 feet.
They can also flood entire neighborhoods, especially in areas of low-lying land.
The Stages of A Hurricane Spinning
There are four stages of a hurricane spinning. Each stage has its own characteristics.
Stage 1 – Formation Stage
This stage lasts for about 24 hours. During this time, the hurricane begins to form.
The hurricane starts out as a small area of low pressure. This low-pressure area slowly grows larger.
Stage 2 – Eye Wall Stage
Once the hurricane becomes big enough, it develops an eye wall. An eyewall is a circular patch of calm air surrounded by a ring of thunderstorms.
It’s important to note that the eye wall is not always present during all phases of a hurricane.
Stage 3 – Rapidly Rotating Cyclone Stage
Once the hurricane reaches this stage, it begins to rotate rapidly. This rapid rotation causes the hurricane to spin faster. At this point, the hurricane is known as a cyclone.
Stage 4 – Super Typhoon/Hurricane Stage
As the hurricane continues to spin, it becomes stronger. When the hurricane reaches this stage it is known as a super typhoon or hurricane.
What Causes Hurricanes To Form?
A tropical depression is formed when a warm front moves through an area of high atmospheric pressure. This warm front is caused by the sun heating up the land mass.
The warm front then pushes away cooler air from the earth. This causes the air above the warm front to become unstable.
A tropical disturbance (see also ‘What Is The Orographic Effect?‘) is created when a tropical depression strengthens into a tropical storm.
Tropical storms are made up of rotating thunderstorms. There are two types of tropical storms:
Cyclonic (Rotating) Storms
Cyclonic, or rotating storms, have one side that faces toward the equator. The other side faces north or south.
Non-Cyclonic (Non-Rotating) Storms
These storms do not rotate. They usually move in a straight line. Tropical depressions are formed when a tropical storm forms.
Depressions are areas of low pressure which are located near the center of a tropical storm. Tropical depressions can be classified into three categories:
Subtropical depressions are similar to tropical depressions except they don’t contain any tropical features such as a central dense overcast.
Transition Zone Depression
Transition zone depressions are similar to subtropical depressions but they are located within 10 degrees latitude of the tropics.
Tropical depressions are located more than 10 degrees latitude from the equator. When a tropical depression forms, it will begin to intensify.
Intensification occurs when the strength of the winds increase and the cloud tops rise higher.
Where Do Hurricanes Spin The Fastest?
The fastest hurricanes spin at speeds between 150 mph and 180 mph.
These fast-moving hurricanes are called super typhoons and get their power from the heat energy generated by the ocean.
There are many factors that determine how powerful a hurricane is, and some of the main elements include:
Wind speed determines how strong a hurricane is. Stronger wind speeds mean a stronger hurricane.
Pressure is measured in millibars. High pressures indicate a strong hurricane while low pressures indicate weak ones.
Size Of Ocean Basin
The size of the ocean basin affects the intensity of the hurricane. If there is less water in the ocean basin, the hurricane will weaken.
Hurricanes form closer to the equator because the temperature difference between the surface of the ocean and the atmosphere is greater.
Sea Surface Temperature
If the sea surface temperature is warmer, the hurricane will strengthen.
Air Mass Flow
Air masses flow around the hurricane causing it to change direction.
The Coriolis effect is the force that makes hurricanes turn clockwise in the northern hemisphere and counterclockwise in the southern hemisphere.
El Nino/La Nina
El Nino and La Nina affect the strength of hurricanes (see also ‘What’s The Difference Between El Nino And La Nina?‘). During El Nino years, the Pacific Ocean becomes warmer.
This causes the jet stream to slow down, allowing for more moisture to enter the Atlantic Ocean. As a result, hurricanes become stronger.
During La Nina years, the Pacific Ocean cools off. This causes the jetstream to speed up, pushing away the moisture. As a result, fewer hurricanes develop.
Water Vapor Content
Water vapor content increases during periods of high humidity. When the air is humid, the water vapor content rises.
What Is A Super Typhoon?
A super typhoon is a very intense tropical cyclone with maximum sustained winds of 195 km/h (120 mi/h).
It has been known to have winds of up to 300 km/h (186 mi/h), making them one of the strongest storms ever recorded.
These are amongst the fastest-spinning of all hurricanes or tropical storms and are usually a major threat to life.
Super typhoons occur when two or more tropical cyclones come together. They can also be caused by an extratropical storm becoming trapped inside the troposphere.
Super typhoons are extremely rare events, occurring only once every 20-30 years.
How Are Hurricanes Detected?
When a tropical depression forms, its location is tracked using satellite imagery.
Satellite images show where the clouds are located, which allows forecasters to track the movement of the storm.
Once a tropical depression reaches tropical storm status, it is given a name.
Once it reaches hurricane status, it is also given an official number to help experts track and identify it, as well as make it easier to talk about and discuss.
Tropical depressions can last anywhere from five days to three weeks before they dissipate, and experts can use the data that they gather to predict how long it will take for the storm to reach hurricane status.
This allows them to give warnings to people who live near the coast.
Why Do Some Storms Become Hurricanes And Others Don’t?
There are many factors that determine whether a tropical system will become a hurricane.
The most important factor is the amount of energy contained within the storm.
Energy is the ability to do work. For example, if you throw a ball into the air, then the kinetic energy of the ball is stored in the potential energy of the ball.
If there is enough energy in the storm, then it will continue to grow until it reaches hurricane status.
However, if there isn’t enough energy, then the storm will not get any bigger than a tropical depression.
Another factor that determines whether a storm will become a hurricane is the size of the storm.
Smaller storms tend to form over warm waters, while larger ones tend to form over cooler waters.
The third factor is the rotation rate of the storm. If the storm rotates quickly, then it will increase in intensity faster than if it spins slowly.
Hurricanes are powerful storms that cause significant damage and loss of life.
Although they can be incredibly serious, they are still possible to prepare for, and having a better understanding of these types of storms allows you to better unlock and understand the world around you.