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Category 5 hurricanes in the Atlantic Basin are somewhat rare,but history has shown there are preferred areas and times of the season they occur most often.
Category 5 hurricanes are those with maximum sustained winds 157 mph or greater on the Saffir-Simpson Hurricane Wind Scale.
These strongest possible hurricanes are capable of catastrophic wind damage,including demolishing many framed homes,downing numerous trees and powerlines and knocking out power,leaving areas uninhabitable for weeks or months,according to the National Hurricane Center.
(MORE:Not Just The Category,There Are Other Important Aspects Of Hurricanes)
How Often They Happen
Thankfully,these top-end hurricanes don't happen that often.
Since 1924,only 37 hurricanes have reached Category 5 status at least briefly in the Atlantic Basin,according to NOAA's database.
That's an average of about one such hurricane every 2 to 3 years.
The last ones to do so were Hurricanes Dorian and Lorenzo in 2019.
Four straight years had at least one Category 5 hurricane from 2016 through 2019,the most consecutive years on record.
Three straight years from 2003 through 2005 also had at least one Category 5 hurricane,led by the historic 2005 season's four Category 5 hurricanes,Emily,Katrina,Rita and Wilma.
But they don't happen every year.
Prior to 2016's Hurricane Matthew,the Atlantic went eight consecutive hurricane seasons without a Category 5. There was another eight-year stretch between Hurricanes Allen and Gilbert from 1980 to 1988.
When They Happen
Category 5 hurricanes have most often happened in September,but have also happened in August and October.
This encompasses the most active period of hurricane seasonThat's because all of the favorable conditions and ingredients for development are most likely to overlap over a large area of the Atlantic Basin.
Hurricane Emily was the earliest Category 5 on record,doing so in the Caribbean Sea on July 16-17,2005. The Cuba hurricane of 1932 was the latest Category 5,the only one to do so in November (Nov. 5-8).
Where They Happen
The map below shows locations where hurricanes have reached Category 5 intensity.
Other than the oddity that was Lorenzo in 2019,you'll notice almost all of them happen in the same general area,from the southwest Atlantic Ocean north of the Lesser Antilles into the Caribbean Sea and Gulf of Mexico.
Twenty of those hurricanes reached Category 5 intensity in the Caribbean Sea. Ten of those did so in the Gulf of Mexico and eight of those did so in the southwest Atlantic Ocean,from the Bahamas to north of the Leeward Islands.
These areas are so conducive to strengthening because they have a supply of deep,warm ocean water,lack hostile shearing winds and feature a parade of disturbances known as tropical waves,which act as seeds for development. The supply of deep,warm ocean water that serves as fuel for hurricanes is highest in the Atlantic Basin in these areas,particularly the western Caribbean Sea.
How Long They Last
On average,a hurricane maintains Category 5 status only about 24 hours.
That's because intense hurricanes typically undergo one or more eyewall replacement cycles. During one of these,the hurricane's intense ring of thunderstorms surrounding its eye is surrounded by a new outer ring.
When that happens,the hurricane's wind intensity drops temporarily as the former eyewall is choked off. It usually intensifies again when the new outer eyewall is pulled inward,leading to a larger hurricane.
Several Category 5 hurricanes reached that intensity multiple times during their lifetime.
Hurricanes Allen (1980),Isabel (2003) and Ivan (2004) each soared to Category 5 intensity three separate times in their journeys.
The November 1932 Cuba hurricane (78 hours) and Hurricane Irma in 2007 (77 hours) spent the longest combined time at Category 5 strength,according to NOAA's database.
How Many Have Made A Mainland U.S. Landfall
Four of these Category 5 hurricanes have made a mainland U.S. landfall.
The most recent of these was Hurricane Michael in the Florida Panhandle in October 2018.
The others include Andrew in 1992 in South Florida,Camille in 1969 on the Mississippi Gulf Coast,and the 1935 Labor Day hurricane in the Florida Keys.
Even if a Category 5 hurricane doesn't maintain that intensity at landfall,it's almost always dangerous.
Since 1955,24 of the 28 hurricanes that did reach that intensity at least briefly in their lifetime were so destructive and/or deadly that their names were retired from future use.
So the next time you hear about a Category 5 hurricane in the Atlantic Basin,know that you're witnessing something that doesn't happen every year and that hurricane is likely to be destructive if it strikes land.
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