Africa Rains
At the start of every cyclone, all youâll find is some showers sweeping off the coast of Africa. 60-85% of the hurricanes youâll encounter a season start at this very place and stage.
Usually, small islands off the coast named the Cabo Verde are impacted by rains from these storms moving off the coast and into the ocean.
Traveling The MDR
After these thunderstorms move off the coast, weather companies notice these as âtropical wavesâ. Tropical waves are thunderstorms in the ocean that have potential to grow stronger as it moves farther westward.
However, there are many factors that lead to the formation of this, and if it doesnât follow all these rules, it will not form.
Water Temperatures: the water it is traveling across must be at least 78 degrees Fahrenheit.
Air Conditions: These thunderstorms will not organize if the air contains Saharan dust. This is why few hurricanes form in July, as Saharan dust is expanding across the MDR.
Frontal Systems: Iff a thunderstorm here interacts with a high pressure system, the thunderstorms will weaken and not form.
Wind Shear: If the storm runs into wind shear, this will weaken it significantly.
Storms can easily grow significantly traveling across the MDR.
For example, Beryl, a late June major hurricane, was able to go from tropical wave status to a Category 5 hurricane just in the MDR. This process is called rapid intensification. We are seeing that now with Hurricane Helene in the Gulf Of Mexico.
A Path To Take
Once the hurricane comes near the Lesser Antilles, it has a decision.
It will either go north, resulting in a mostly âfish stormâ (a storm that spends its life out to sea).
However, sometimes the path can shift westward far after, and result in a potential Canadian threat.
The hurricane can also make landfall in the Lesser Antillies, continuing a western slide.
Unfortunately, these small islands often aren't big enough to significantly weaken the storm, and the storm may continue strengthening in the Caribbean. Now it has to make landfall. This will either take place on a Caribbean island, or it will go further into the Gulf Of Mexico.
Lastly, it could shift northwest and impact the Atlantic seaboard.
Pre-Landfall and Landfall
For the best understanding, lets use a hypothetical scenario:
This storm takes the Caribbean path in September. Right now it is organized enough to be considered a named tropical storm as it passes the Lesser Antillies. The Caribbean waters are very warm at this time of year, and often share plenty of moisture. Now you've got a hurricane on your hands by the time it approaches the Gulf Of Mexico. The heated, deep waters at this time are perfect for a hurricane to strengthen. The Category 2 hurricane is now going to reach major hurricane status, if nothing at the time is blocking it like the common conflict of wind shear, preventing much strength of the storm.
So, it makes landfall in Florida as a major hurricane.
A major hurricane is going to bring winds of 111+ MPH. A Cat 5 could even be 157+. For comparison, what you call a windy day is 20 MPH.
The flooding gets even crazier. The storm surge, which is the amount of water getting pushed onto land, is 9-18 feet of water. An average house stands 20 feet high.
This causes 10s of billions of dollars in damage.
Aftermath
After the storm interacts with land, there will be no moisture for it to collect, causing it to quickly weaken. By the time it goes far inland, all that is left is rain and maybe some winds.
The areas affected by the storm lay in ruins. It's described like an EF 1 or 2 tornado has hit the space â but hundreds of miles wide.
If the storm's remnants were to precipitate in the rocky mountains areas in the fall months, sometimes this can cause heavy snow.