Hurricane? What is it? How does it form?
If you are on my blog, you have seen me mention hurricanes. But what exactly is a hurricane? How do they form?
Not a lot of people know the answers, because we rely on things like the weather channel to tell us if we are in danger. While it is always preferred to listen to the professionals, it’s never a bad thing to know what the professionals are talking about.
So how DOES a hurricane form?
Well the first thing you should know is that first, they start off as a group of large thunderstorms, called a Tropical Disturbance/Depression.
These come off the west coast of Africa and travel towards us, following the Northeasterly Trade Winds (NTW) and the North Equatorial Current (NEC).
The NTW is an air current that moves off africa and goes westward along the equator, which is the imaginary line that is drawn around the earth equally distant from both the top and bottom of the planet.
The NEC is an ocean current that carries warm ocean water from the coast of Africa, up through the Caribbean. This warm water is then heated even more as it enters the Caribbean, which is an area of super warm ocean water.
*The Caribbean Sea just experienced record breaking heat waves in 2023, with water temperatures reaching 90°F, which is more than 2 degrees above average, which may not seem like a lot, but every degree matters.*
Both of these currents work together to create what is referred to as a highway for hurricanes.
As those thunderstorms are pulled by the currents, they begin to build and become bigger and more powerful because they feed on warm moist air, which is plentiful in that area of the world.
As the thunderstorms group together and grow, warm moist air is pulled up into the storm, and the cold unstable air at the top settles back down to the surface on the outsides of the storm, which are then heated and go through the cycle again and again.
Now, because moist air is less dense than dry air, and the warm air is consistently rising, this creates an area of low pressure. As the storm becomes more intense and the wind speeds increase, the pressure drops even further. The atmospheric pressure is measured using a barometer, and it is displayed in units called Millibars (mb).
As the wind speeds increase and get to a speed of 40 MPH the Tropical Disturbance/Depression is then upgraded to a Tropical Storm.
Once the storm gets large enough and has started to really draw up some power from the moist humid air beneath it, and the pressure starts dropping, the Coriolis Force will cause the development of a low-pressure center.
The Coriolis Force is a physics term for an inertial force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame….WHAT? I know, that’s a lot of mumbo jumbo if you don't understand physics, so let’s just say it’s because of the way the earth spins that it then causes the storms to spin, make sense?
Once a low-pressure center develops, it creates an eye. Now this eye can be what is called either a clean eye, or a dirty eye. A dirty eye is just one that contains storms within it. A clean eye is commonly seen with hurricanes, and it is the section of the middle that is partially if not completely clear.
Now this eye will be sucking up warm moist air like drinking through a straw.
Once the wind speeds get above 74 MPH, then it is officially considered a Hurricane.
Keep in mind!! The wind speeds are measured in SUSTAINED wind speeds, so that means the wind is blowing at that speed consistently for a significant period of time. This does not include gusts, as random wind gusts can even be double the sustained wind speed.
The wind speeds are what define how strong a hurricane is, as shown below. This is called the Saffir Simpson Wind Scale.
So that's pretty much how they form, and they can get very very strong.
Not only do you have to worry about wind speeds, but you have to worry about rainfall, storm surge and even tornadoes...!
Yes, you read that correctly, tornadoes can come from hurricanes, in fact, it is very common! So it is very important that if there is an evacuation order and you are able to leave, please find a way to do so. Do not put yourself in harm's way.
If you have any questions about hurricanes, feel free to send me a message, an ask, anything...and I will be happy to answer it to the best of my ability.
