Editor’s Note (10/9/24): Hurricane Milton made landfall on October 9th around 8:30 PM EDT near Siesta Key, Florida. At that time, Milton It was a Category 3 storm with sustained winds of about 120 mph. Hurricane Milton is traveling east-northeast across the Florida peninsula. Its center is expected to reach the Atlantic Ocean tomorrow. Bermuda may experience the effects of the storm on October 12 and October 13, but Milton will not hit the eastern US.
Editor’s Note (10/9/24): This story is being updated as the situation develops.
It’s still clearing in parts of Florida Hurricane Helene damage two weeks agoA second damaging storm, Hurricane Milton, is wreaking further havoc.
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Milton made landfall around 8:30 p.m. EDT on October 9 near Siesta Key, Fla Category 3 storm With maximum sustained winds of 120 kilometers per hour. He suffered explosively rapid intensification on Monday, in the Gulf of Mexico, reaching winds of 180 kilometers per hour. Its central pressure—another measure of strength—dropped to 897 millibars, making it the fifth strongest hurricane ever recorded in the Atlantic basin.
Milton headed northeast, directly toward the west coast of Florida. The worst impact was expected to occur around Tampa, but the storm moved south. The first of Hurricane Milton’s rains hit Florida on October 9 Tampa Bay worst hit by a major storm in a centuryalthough the region, home to more than three million inhabitants, is no stranger to hurricane damage.
“This is a very serious situation,” says Rick Davis, a meteorologist at the National Weather Service’s Tampa Bay office. “It’s going to affect a lot of people in the state of Florida.” On October 8, US Health and Human Services Secretary Xavier Becerra declared a state of emergency for all of Florida as of October 5. About 5.5 million people were told. evacuate in anticipation of the hurricane making landfall.
Hurricane Milton was expected to bring a wide range of threats to west-central Florida: strong winds, power outages that could last up to a week, storm surges Between 10 and 13 feet and six to 12 inches of rain, with some places getting as much as 18 inches. Tornadoes were also expected, and The National Weather Service issued about 100 tornado warnings on October 9 in just six hours, he says Washington Post. All of this comes two weeks after Hurricane Helene, which made landfall more than 100 miles from Tampa Bay but still wreaked havoc in the region, producing the largest storm surge since records began in 1947.
Tampa Bay is inherently vulnerable to storm surge because the seawater is relatively deep, with water only inland. Additionally, Hurricane Milton was expected to land at a right angle and hit the Florida coast head-on. While reaching at a more oblique angle can push the water along the coast, a perpendicular arrangement causes a stronger upwelling because it only pushes the water inland. The latter would “accumulate the water faster and faster and not allow it to recede,” says Davis.
Additionally, Helen removed local defenses such as sand dunes, leaving the region more vulnerable to future surges. The strongest storm surge today was expected to hit south of Tampa, but Hurricane Milton could still produce a stronger storm surge around Tampa Bay than Hurricane Helene. (Hurricane Helene killed at least 230 people in the southeastern United States, including 19 in Florida. A dozen of the latter occurred in the Tampa Bay region.)
The area is also particularly vulnerable to flooding right now, both on the coast and inland. Even before Helene hit, the area had a particularly wet summer, Davis says, leaving the ground saturated and rivers overflowing. Then came Helene’s gusts and showers; has The storm also scattered debris and pushed sand into the area’s stormwater drains, making the region even less able to absorb the additional water.
Residents of Pinellas County, Florida celebrate John Chesnut Sr. on October 6, 2024. Sandbags in the park in Palm Harbor, Florida. Florida’s governor declared a state of emergency on October 5 after forecasters warned that Hurricane Milton would make landfall. later this week.
Bryan R. Smith/AFP via Getty Images
When Milton approached Florida, the intensity of its hurricane at landfall was particularly unexpected because it underwent a process called rapid intensificationthe most sustained winds of a storm increase in speed by at least 35 kilometers per hour in a 24-hour period.
Hurricane Milton blew that definition out of the water. “It went from Category 1 to Category 5 in 18 hours,” says Kristen Corbosiero, an atmospheric scientist at the University at Albany. “It’s a really scary situation.” As of noon EDT on October 7, the storm’s maximum sustained winds were 175 mph; the previous morning its winds were only 65 kilometers per hour. according to New York Times, Only two Atlantic hurricanes, Wilma in 2005 and Felix in 2007, have been recorded to have experienced larger jumps in intensity within a 24-hour period.
Climate change is expected to increase the number of storms. It’s too early to tell exactly what role climate change has played throughout the season, but other hurricanes this year, including hurricanes. berylFrancine and Helene, too, suffered a rapid life. And like Hurricane Helene, Milton has been fueled by the exceptionally warm waters that have characterized the Gulf of Mexico this year. Scientists have already determined that climate change increased the severity of the Helene rains and that the warm ocean water that fueled the storm is 200 to 500 times more likely.
Hurricane Milton began as an organized tropical cyclone. “It’s been quite a dense hurricane. At one point it had what we call a pinhole eye, which is a very small eye,” says Anantha Aiyyer, an atmospheric scientist at North Carolina State University.
Later, Hurricane Milton completed what scientists call an eyewall replacement cycle, which caused the storm to weaken some but grow in size. In the process, a storm builds a new eyewall, with strong winds forming a heart that surrounds the existing core. Within a day, the original eyewall may collapse, giving way to the new structure.
A satellite image shows Hurricane Milton approaching the west coast of Florida over the Gulf of Mexico on October 9, 2024.
CIRA/NOAA/NESDIS/STAR GOES-East
This is not of academic interest: the process of eyewall replacement allows storm clouds—and damage—to cover more ground. “What’s really concerning with these eyewall replacement cycles is that the storm’s wind field grows,” says Corbosiero. The National Hurricane Center predicted Milton’s tropical-storm-force winds could double in the early hours of October 8 as it approaches Florida.
On the afternoon of October 9, Milton began to find additional wind shear, meaning the storm structure is experiencing winds coming from different directions at different speeds. The phenomenon breaks into a tropical cyclone, weakening the storm that happened with Milton. But this weakening had little effect on damage forecasts. The storm is expected to weaken further as it moves over land, but significant damage from winds, gusts and rain is expected to continue.
Before making landfall, the storm was also expected to undergo a phenomenon called an extratropical transition, which is when a hurricane leaves the tropical atmosphere and begins to encounter atmospheric patterns more typical of cooler environments. “You’re going from this more uniform, hot, humid environment to one that has a lot of contrast,” says Allison Michaelis, an atmospheric scientist at Northern Illinois University. It’s a common change when a storm moves north, although Milton is moving a bit further south than many, he says.
The best example of an extratropical transition is Hurricane Sandy in 2012. The phenomenon tends to make hurricanes a little less orderly—the winds tend to weaken, but the storms also tend to be larger, exposing more land and people to severe winds and rain, Aiyyer and Michaelis say. The process can also be changed to where the strongest winds occur. “The storm is adapting its identity from a tropical storm to an extratropical storm,” says Aiyyer, because of its cold core and less symmetrical structure.
Hurricane Milton is expected to complete this transition by or after its time in Florida ends, Michaelis says, so different precipitation patterns for these types of storms aren’t likely to change the impacts people should expect on the ground. And unlike the notorious Hurricane Sandy, Milton doesn’t appear to have any atmospheric flow that could carry it ashore to wreak havoc on the US East Coast after leaving Florida.
As Milton evolved, it was clear that no particular feature of the atmosphere was likely to significantly alter the severity of the hazards experienced by the region. And Tampa Bay is known to be particularly vulnerable to severe hurricanes, which it usually experiences only peripherally. “We’ve been hit by many, many, many, many storms,” Davis says. But the last time a major hurricane made landfall in the region was in 1921. Since 1946 it has not seen the direct impact of any hurricane. Milton can break that trend.
After hitting the west-central coast of Florida, Hurricane Milton is expected to cross the state and then cross the Atlantic Ocean. Parts of the Georgia coast are under a tropical storm warning, meaning tropical storm conditions are expected within 36 hours. Meanwhile, tropical storm conditions are possible in other parts of Georgia and coastal South Carolina over the next 48 hours. Bermuda could also be affected over the weekend, although the storm’s path further south could spare the island. (On October 7 and 8, before Milton made landfall in Florida, the storm was forecast to produce four to six feet of storm surge and two to three inches of rainfall on the Yucatan Peninsula.)
In Florida, however, the risks are very real. “I want people to take this more seriously than they take any other storm,” Davis says. “It will be a storm that people will not forget.”
Corbosiero echoes this concern, especially given that Milton is so close to Helen and her harm. “This really has the potential to be the worst hurricane disaster in US history,” he says. “It’s such a dire situation, especially if it makes a direct hit on Tampa or a heavily populated area on (Florida’s) west coast.”
Editor’s note (10/9/24): An earlier version of this story was published on October 7.
