Once a tropical storm strengthens into a hurricane, it earns a category designation on the Saffir-Simpson Hurricane Wind Scale: 1 through 5.
The categories are defined by wind speed, with a storm of Category 3, 4, or 5 considered a major hurricane. And damage is exponential as wind speed increases, meaning a strong Category 3 storm could do up to 60 times as much damage as a weak Category 1 storm.
Hurricanes carry many risks not adequately conveyed by the wind speed-based scale, including:
• Rainfall-induced flooding and mudslides, which made up about a quarter of such deaths, the report shows;
• A storm’s forward speed: Slower storms are more destructive, with strong gusts or rainstorms that pound the same areas for hours or days;
Sustained winds are enough to blow shingles off roofs and damage gutters and vinyl siding, the National Oceanic and Atmospheric Administration said.
These winds also can uproot trees and bring down branches, causing power outages and more property damage. They can damage power lines directly, too.
Sustained winds could cause as much as 20 times the damage as those of a Category 1 storm, including extensive damage to a home’s roof and siding.
Numerous trees and power lines will most likely be damaged, blocking roads, damaging property and knocking out power for days, if not weeks.
Now in “major hurricane” territory, wind damage is much more widespread. Well-built homes and other buildings could suffer major damage, and roofs will sustain heavy damage. Numerous trees will be damaged or uprooted.
“Electricity and water will be unavailable for several days to weeks after the storm passes,” NOAA said.
Storm surge was estimated at close to 20 feet along the Mississippi-Alabama border, and estimated winds reached as high as 140 mph near Grand Isle, Louisiana. Levee breaches sent water flooding into much of New Orleans, forcing people onto rooftops for rescue. Katrina killed more than 1,800 people, left as many as 600,000 households displaced for at least a month and became the most costly storm on record, according to NOAA.
Catastrophic damage can result from these winds. Well-built homes will be heavily damaged, with most of the roof blown away. Trees and power lines will be down. Water and power services could be out for months, with the hardest-hit places uninhabitable for weeks.
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A broken section of road and destroyed houses are seen in Matlacha, Florida, on Saturday, October 1.
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President Joe Biden and first lady Jill Biden talk to people impacted by Hurricane Ian in Fort Myers, Florida, during a tour of the area on Wednesday, October 5.
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Greg Guidi, left, and Thomas Bostic unload supplies from a boat on Pine Island, Florida, on Tuesday, October 4. With the roads onto the island made impassable, people were getting supplies to the island by boat.
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Members of a search-and-rescue team comb through the wreckage on Fort Myers Beach on Tuesday.
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Stephanie Fopiano, right, gets a hug from Kenya Taylor, both from North Port, as she gets emotional about her situation at the Venice High School hurricane shelter in Venice, Florida, on Monday, October 3.
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Workers and residents clear debris from a destroyed bar in Fort Myers on Saturday, October 1.
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Beachgoers look at a large shrimping boat that was swept ashore in Myrtle Beach, South Carolina, on Saturday.
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Local muralist Candy Miller, left, embraces Ana Kapel, the manager of the Pier Peddler, a gift shop that sold women's fashions, as she becomes emotional at the site where the store once stood on Fort Myers Beach on Friday.
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Waters from a rain-swollen pond cover grass and a foot path around Quarterman Park in North Charleston, South Carolina, on Friday.
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Members of the US Army National Guard help people evacuate from flood waters in North Port, Florida, on Friday, September 30.
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Water streams past buildings on the oceanfront on Sanibel Island, Florida, on Friday.
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University of Central Florida students use an inflatable mattress as they evacuate an apartment complex in Orlando, Florida, on Friday, September 30.
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A firefighter examines a fallen tree in Charleston, South Carolina, on Friday.
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A man tows a canoe through a flooded street of his neighborhood in New Smyrna Beach, Florida, on Friday.
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People wait in line to enter a Home Depot store in Cape Coral, Florida, on Friday. Many in Florida were still without power.
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The wreckage of a car teeters on a buckled roadway on Friday in Matlacha, Florida.
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Members of the Texas A&M Task Force 1 Search and Rescue team look for anyone needing help on Friday in Fort Myers, Florida.
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A man takes photos Thursday, September 29, of boats that were damaged by Hurricane Ian in Fort Myers, Florida.
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Bob Levitt returns to his condemned home to retrieve his cat, which he found hiding in a bedroom Thursday in Palm Beach County, Florida. A tornado spawned by the hurricane left residents homeless.
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This aerial photo shows damaged homes and debris in Fort Myers Beach on Thursday.
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Jake Moses and Heather Jones explore a section of destroyed businesses in Fort Myers Beach, Florida, on Thursday.
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Workers in Naples, Florida, clean up debris on Thursday.
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A section of the Sanibel Causeway is seen on Thursday after it collapsed due to the effects of the storm.
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Stedi Scuderi looks over her flooded apartment in Fort Myers on Thursday.
From Orange County Government
A resident of Orange County, Florida, and a couple of dogs are rescued from floodwaters on Thursday.
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A boat lies partially submerged in Punta Gorda, Florida, on Thursday.
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Tom Park begins cleaning up in Punta Gorda on Thursday.
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Residents of Port Charlotte, Florida, line up for free food that was being distributed from a taco truck on Thursday.
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A causeway to Florida's Sanibel Island is seen on Thursday. The causeway is the only way to get to or from Sanibel and Captiva Islands to Florida's mainland.
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People clear a large tree off their home in Fort Myers on Thursday.
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Homes are flooded in Port Charlotte on Thursday.
Amy Beth Bennett/South Florida Sun-Sentinel/AP
Jonathan Strong dives into floodwaters while he and his girlfriend, Kylie Dodd, knock on doors to help people in a flooded mobile home community in Iona, Florida, on Thursday. "I can't just sit around while my house is intact and let other people suffer," he said. "It's what we do: community helping community."
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Brenda Brennan sits next to a boat that pushed up against her apartment building in Fort Myers on Thursday. She said the boat floated in around 7 p.m. Wednesday.
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People walk along the beach looking at property damaged in Bonita Springs, Florida, on Thursday.
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An Orlando resident is rescued from floodwaters on Thursday.
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Vehicles make their way through flooded streets in Fort Myers on Thursday.
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Stefanie Karas stands in her flooded apartment in Fort Myers on Thursday. She is an artist and was salvaging what she could from her home.
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Heavily damaged homes are seen on Sanibel Island on Thursday.
Douglas R. Clifford/Tampa Bay Times/ZUMA Presss
A spiral staircase lies next to a damaged pickup truck in Sanibel, Florida, on Thursday.
Marco Bello/Reuters
A flooded street is seen in downtown Fort Myers after Ian made landfall on Wednesday, September 28.
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A woman surveys damage through a door during a power outage in Fort Myers on Wednesday.
NOAA/NASA
A satellite image shows the hurricane making landfall on the southwest coast of Florida on Wednesday.
Naples Police
The streets of Naples, Florida, are flooded on Wednesday. City officials asked residents to
shelter in place until further notice.
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A woman is helped out of a muddy area Wednesday in Tampa, Florida, where
water was receding due to a negative storm surge.
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Strong winds hit Punta Gorda on Wednesday.
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A woman holds an umbrella inverted by the wind in Tampa on Wednesday.
Pedro Portal/El Nuevo Herald/TNS/Abaca/Reuters
Sailboats anchored in Roberts Bay are blown around in Venice, Florida, on Wednesday.
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Melvin Phillips stands in the flooded basement of his mobile home in Stuart, Florida, on Wednesday.
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Damage is seen at the Kings Point condos in Delray Beach, Florida, on Wednesday.
Officials believe it was caused by a tornado fueled by Hurricane Ian.
Marco Bello/Reuters
A TV crew broadcasts from the beach in Fort Myers on Wednesday.
Stephen M. Dowell/Orlando Sentinel/AP
Utility trucks are staged in a rural lot Wednesday in The Villages, a Florida retirement community.
Shannon Stapleton/Reuters
Highways in Tampa are empty Wednesday ahead of Hurricane Ian making landfall. Several coastal counties in western Florida were under mandatory evacuations.
Wilfredo Lee/AP
An airplane is overturned in Pembroke Pines, Florida, on Wednesday.
Joe Cavaretta/South Florida Sun-Sentinel via AP
Zuram Rodriguez surveys the damage around her home in Davie, Florida, early on Wednesday.
Ramon Espinosa/AP
People play dominoes by flashlight during a blackout in Havana, Cuba, on Wednesday. Crews in Cuba have been working to restore power for millions after the storm battered the western region with high winds and dangerous storm surge,
causing an islandwide blackout.
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People walk through a flooded street in Batabano, Cuba, on Tuesday.
Chris O'Meara/AP
Southwest Airlines passengers check in near a sign that shows canceled flights at the Tampa International Airport on Tuesday.
Ramon Espinosa/AP
Maria Llonch retrieves belongings from her home in Pinar del Rio, Cuba, on Tuesday.
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Traffic builds along Interstate 4 in Tampa on Tuesday.
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A man carries his children through rain and debris in Pinar del Rio on Tuesday.
Alexandre Meneghini/Reuters
People drive through debris in Pinar del Rio on Tuesday.
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Frederic and Mary Herodet board up their Gulf Bistro restaurant in St. Pete Beach, Florida, on Tuesday.
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NASA's Artemis I rocket rolls back to the Vehicle Assembly Building at the Kennedy Space Center in Cape Canaveral, Florida, on Tuesday. The launch of the rocket was postponed due to the impending arrival of Hurricane Ian.
NASA via AP
Hurricane Ian is seen from the International Space Station on Monday, September 26.
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A Cuban family transports personal belongings to a safe place in the Fanguito neighborhood of Havana on Monday.
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A family carries a dog to a safe place in Batabano on Monday.
Phelan M. Ebenhack/AP
People wait in lines to fuel their vehicles at a Costco store in Orlando on Monday.
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Ryan Copenhaver, manager of Siesta T's in Sarasota, Florida, installs hurricane panels over the store's windows on Monday.
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A man helps pull small boats out of Cuba's Havana Bay on Monday.
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Shelves are empty in a supermarket's water aisle in Kissimmee on Monday.
Martha Asencio-Rhine/Tampa Bay Times via ZUMA Press Wire
Cathie Perkins, emergency management director in Pinellas County, Florida, references a map Monday that indicates where storm surges would impact the county. During a news conference, she urged anyone living in those areas to evacuate.
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Sarah Peterson fills sandbags in Fort Myers Beach on September 24.
Ian brought record storm surge to Fort Myers and Naples, estimated at 10 to 15 feet, NOAA said. For days after landfall, the storm dumped unprecedented volumes of rain across Florida, triggering tremendous river flooding in the weeks that followed.
These are the most powerful storms on Earth. Most well-built homes will be destroyed, many stripped to the foundation. Power outages could last for months, and the areas hardest hit could be uninhabitable for months.
• Hurricane Andrew in August 1992 was one of the worst storms to ever hit the United States, devastating a whole region after it made landfall near Homestead, Florida. Andrew grew from a Category 1 storm to a Category 5 storm in just 36 hours, with maximum winds near Homestead around 165 mph, according to NOAA.
At the time, Andrew was the “costliest and most damaging hurricane ever to hit the United States,” the National Weather Service said.