The New York Times News Service
Meteorologists were glued to their computers Monday morning, watching virtual data as the Air Force Reserve Hurricane Hunter aeroplane made pass after pass through the eye of Hurricane Milton. Every time it did, it found the storm’s pressure had dropped, and the eyewall wind speeds had increased, indicating that it was becoming more intense by the minute.
The hurricane went from a Category 1 storm at midnight to a Category 5 hurricane by noon. And it didn’t stop there.
By 8 p.m. Monday, the storm’s maximum sustained wind speeds had increased to 180 mph, making Milton one of the strongest Atlantic hurricanes ever. Based on wind speed, it joined a handful of other hurricanes to rival the strongest Atlantic storm ever recorded: a 1980 hurricane named Allen, which had a peak wind speed of 190 mph before it made landfall along the United States-Mexico border.
As a small, compact system, however, Milton was more similar to Hurricane Wilma in 2005, which holds the record for the lowest pressure in a hurricane, another measure of a storm’s intensity.
Its small size, an excess of extremely warm waters in the Gulf of Mexico and calm atmospheric conditions allowed Milton to "explosively” intensify, as hurricane centre forecasters noted Monday afternoon.
The standard meteorological definition of rapid intensification is 30 knots in 24 hours or roughly 35 mph daily. Milton increased by more than double this definition Monday, at a pace similar to that of Wilma and another record storm, Hurricane Felix, in 2007.
Hurricane Rita, which reached 180 mph wind speeds in 2005, created extensive damage when it made landfall in Louisiana, blowing windows out of buildings and pushing a strong surge inland. Rita packed a punch despite weakening to a Category 3 before landfall, something Milton is also likely to do as it nears Florida.
At some point, Milton will stop intensifying.
Most Category 5 storms weaken through an eyewall replacement cycle, when a new wall of thunderstorms begins to form around the smaller inner eyewall, choking out its moisture source and creating a much larger eye of the hurricane.
This occurred overnight, reducing Milton’s wind speeds back to Category 4 strength Tuesday morning. That evolution will likely cause Milton, which was fairly tiny Monday, to grow physically larger but gradually weaken Tuesday.
It had to go through an eyewall replacement cycle soon, Phil Klotzbach, a hurricane expert at Colorado State University, said Monday afternoon.
After an eyewall replacement cycle, a storm usually intensifies again, as Milton may do slightly on Tuesday. However, the turbulent conditions in the eastern Gulf of Mexico - called wind shear, or the change of airspeed and direction with height - may limit its ability to strengthen and may even weaken the storm further.
This same interaction may again cause the storm to grow, making the system a large and powerful hurricane at landfall in Florida, with life-threatening hazards at the coastline and well inland.
"This is a very serious situation,” forecasters from the National Hurricane Center said Tuesday morning, warning that "Milton has the potential to be one of the most destructive hurricanes on record for west-central Florida.”
When a storm grows larger, the surge can increase as the winds cover a greater distance from its centre. The wind helps create the surge, which acts similarly to pushing water with your finger; now, imagine how much water you could push with your arm instead.
Here’s how changes in the storm’s path could affect residents.
As the storm approaches Florida in the coming days, its most likely path, as of Tuesday morning, is through the central part of the state. The exact path it takes will have huge ramifications over where the storm surge will hit, and where it won’t.
For example, if the storm is tracking toward the northeast and makes landfall just west of Tampa Bay, the surge will push right through up the mouth of the bay. If the storm makes landfall farther south, Tampa Bay might be spared, but anywhere south of the centre path of the storm will have a terrible surge.
Another thing to consider is that another area of disturbed weather has been bringing flooding rains to the Florida Peninsula ahead of Milton. As the state just saw with Hurricane Helene, devastating effects can occur when rain falls before a hurricane’s landfall. The amount of rain that falls will depend on how quickly the storm moves across the peninsula and where it makes landfall.