The only thing 100% predictable about hurricanes is their constant changes.
These atmospheric phenomena, which are formed with the energy of warm waters and winds, represent a challenge for meteorologists due to their instability.
It is necessary to follow them minute by minute through radars and satellites to predict their behavior, and thus prepare for any eventuality that represents a risk.
And one of the changes that most surprises experts is the so-called hurricane eyewall replacement.
This event, which usually occurs in large Category 3, 4 and 5 hurricanescan change the effects of a cyclone once it makes landfall.
Hurricane Milton, which reached category 5 on Monday with sustained winds of 285 km/h, He weakened this Tuesday as he entered his eye replacement cycle.
The US National Hurricane Center (NHC) reported that, based on its observations, “Milton completed an eyewall replacement overnight. (…) However, it does not seem that the hurricane has weakened much after the replacement.”
According to the NHC, it may even be regaining strength.
This occurred while moving through the warm waters of the Gulf of Mexico towards the Florida peninsula.
The first thing you should know is that hurricanes have a structure that is divided into three parts: the eye, the eyewall and the rain bands.
In the rain bands there are clouds and strong thunderstorms that move in a spiral, producing winds and sometimes tornadoes. While, the eye is an area of relative calma center around which the precipitation bands rotate.
AND the wall is precisely the area closest to the eye. “The eyewall consists of a ring of high thunderstorms that produce heavy rain and typically the strongest winds,” explains the NHC about this hurricane zone.
Changes in the structure of the eye or its wall can make a cyclone’s winds stronger or weaker. “The eye can grow or shrink in size and double walls can form,” notes the NHC.
Wall replacement and its effects
The replacement of the eyewall usually occurs in high intensity hurricanes, meteorologist Ernesto Rodríguez, from the US National Weather Service, explained to BBC Mundo.
These cyclones, which range from category 3 to 5 on the Saffir-Simpson scale, have sustained winds of more than 178 km/h.
As hurricanes intensify, the eye walls become narrower and more intense until they reach maximum strength for the available energy.
At this point, a new eye wall may begin to form on the outside of the inner wall of the old eye, cutting off fuel for the inner wall and eventually causing it to disappear.
“What happens is that a larger wall of thunderstorms begins to surround and suffocate the inner core that had originally formed. The new ring of storms surrounds the oldest eyewall and it eventually disappears,” Rodríguez explained.
When hurricanes go through this process, which usually happens while they are strengthening, they momentarily stop gaining strength.
“They go through cycles in which the eye changes diameter. eye replacement keeps them [a los huracanes] stable and then intensify again”Rodriguez added.
Eyewall replacement can take 12 to 18 hours or up to two to three days to complete, and these cycles can occur several times the life of a tropical cyclone.
After Hurricane Milton went through its eye replacement cycle, experts predict that it will gain strength again this Tuesday.
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