The Gulf Coast braced Sunday for a potentially devastating hit from twin hurricanes as two dangerous storms swirled toward the U.S from the Gulf of Mexico and the Caribbean. Officials feared a history-making onslaught of life-threatening winds and flooding along the coast, stretching from Texas to Alabama.
A storm dubbed Marco grew into a hurricane Sunday as it churned up the Gulf of Mexico toward Louisiana. But, Marco's intensity was fluctuating, forecasters said, and the system was downgraded to a tropical storm Sunday night.
Another potential hurricane, Tropical Storm Laura, lashed the Dominican Republic and Haiti, and was tracking toward the same region of the U.S. coast, carrying the risk of growing into a far more powerful storm.
Experts said computer models show Laura could make landfall with winds exceeding 110 mph (177 kph), and rain bands from both storms could bring a combined total of 2 feet (0.6 meters) of rain to parts of Louisiana and several feet of potentially deadly storm surge.
"There has never been anything we've seen like this before, where you can have possibly two hurricanes hitting within miles of each over a 48-hour period," said Benjamin Schott, meteorologist in charge of the National Weather Service's Slidell, Louisiana, office.
The combination of the rain and storm surge in a day or two means "you're looking at a potential for a major flood event that lasts for some time," said weather service tropical program coordinator Joel Cline. "And that's not even talking about the wind.''
Where precisely Marco was headed â and when the storm might arrive â remained elusive Sunday. Marco was initially expected to make landfall Monday, but the National Hurricane Center said that "a major shift" in a majority of their computer models now show the storm stalling off the Louisiana coast for a few days before landing west of New Orleans â and likely weakening before hitting the state. However, skeptical meteorologists at the center were waiting to see if the trends continue before making a dramatic revision in their forecast.
A look at the 10 costliest hurricanes to ever hit the US
A look at the 10 costliest hurricanes to ever hit the US
1. Hurricane Katrina, 2005
UpdatedAll data is from the National Hurricane Center. Numbers from 1900-2020 are taken from the NHC's report on "The Deadliest, Costliest and Most Intense U.S. Tropical Cyclones."
All damage numbers are adjusted for inflation to 2020 USD. Reported deaths are for the U.S. only.
Total cost of damages:Â $170 billion
Storm category: 3
Deaths attributed to storm in the U.S. (both direct and indirect*): 1,833
Only partial framing remains of houses in a residential community along the Jourdan River, north of Bay St. Louis, Miss., after being devastated by Hurricane Katrina on Thursday, Sept. 8, 2005. (AP Photo/M. Spencer Green)
*Deaths occurring as a direct result of the forces of the tropical cyclone are referred to as âdirectâ deaths, according to the National Hurricane Center. These would include those persons who drowned in storm surge, rough seas, rip currents, and freshwater floods. Direct deaths also include casualties resulting from lightning and wind-related events (e.g., collapsing structures). Deaths occurring from such factors as heart attacks, house fires, electrocutions from downed power lines, vehicle accidents on wet roads, etc., are considered âindirectâ deaths.
2. Hurricane Harvey, 2017
UpdatedTotal cost of damages:Â $131.3 billion
Storm category: 4
Deaths attributed to storm: 103
People launch boats from an overpass into floodwaters in the aftermath of Tropical Storm Harvey in Kountze, Texas, Thursday, Aug. 31, 2017. (AP Photo/Gerald Herbert)
3. Hurricane Maria, 2017
UpdatedTotal cost of damages: $94.5 billion
Storm category: 4
Deaths attributed to storm: Officially, the Puerto Rican death toll remained at 65 for months after the storm, according to NHC reports. A Harvard University study estimated the number of deaths in Puerto Rico to actually be between 800 and 8,500.
Additionally, there were 31 deaths in Dominica with another 34 people missing, two deaths in Guadeloupe, two in St. Thomas, five in the Dominican Republic, three in Haiti, and four on the U.S. mainland.
People sit on both sides of a destroyed bridge that crossed over the San Lorenzo de Morovis river, in the aftermath of Hurricane Maria, in Morovis, Puerto Rico, Wednesday, Sept. 27, 2017. A week since the passing of Maria many are still waiting for help from anyone from the federal or Puerto Rican government. But the scope of the devastation is so broad, and the relief effort so concentrated in San Juan, that many people from outside the capital say they have received little to no help. (AP Photo/Gerald Herbert)
4. Hurricane (Super Storm) Sandy, 2012
UpdatedTotal cost of damages: $74.1 billion
Storm category: 1
Deaths attributed to storm: 159
The sun rises in Seaside Heights, N.J., Monday, Feb. 25, 2013, behind the Jet Star Roller Coaster which has been sitting in the ocean after part of the Funtown Pier was destroyed during Superstorm Sandy. The private owners of the amusement pier that collapsed in Seaside Heightsare working with insurers to devise a plan to dismantle the ride and get it out of the ocean. (AP Photo/Mel Evans)
5. Hurricane Irma, 2017
UpdatedTotal cost of damages: $52.5 billion
Storm category: 4
Deaths attributed to storm: 92
A house rests on the beach after collapsing off a cliff from Hurricane Irma in Vilano Beach, Fla., Friday, Sept. 15, 2017. (AP Photo/David Goldman)
6. Hurricane Andrew, 1992
UpdatedTotal cost of damages: $50.5 billion
Storm category: 5
Deaths attributed to storm: 65
A resident in Homestead, Fla., asks for help for the entire block, Aug. 26, 1992, after the area was ravaged by Hurricane Andrew earlier in the week. The sign on the roof reads "Help please! The block needs H20, can food, ice, gas, building supplies." Homestead was one of the hardest hit areas in the wake of the storm. (AP Photo/Lynne Sladky)
7. Hurricane Ike, 2008
UpdatedTotal cost of damages: $36.9 billion
Storm category: 2
Deaths attributed to storm: 113
FILE - In this file photo taken Sept. 12, 2008, a boarded up home sits along the beach as Hurricane Ike approaches Galveston, Texas. (AP Photo/David J. Phillip, File)
8. Hurricane Ivan, 2004
UpdatedTotal cost of damages: $28.7 billion
Storm category: 3
Deaths attributed to storm: 57
An SUV is seen covered by sand as residents walk to their homes to inspect the damage by hurricane Ivan Wednesday, Sept. 22, 2004 in Pensacola Beach, Fla. Beach residents were allowed to see their homes for the first time since the hurricane. (AP Photo/Alan Diaz)
9. Hurricane Wilma, 2005
UpdatedTotal cost of damages: $25.8 billion
Storm category: 3
Deaths attributed to storm:Â 5 (direct only)
Residents look over damage caused by Hurricane Wilma to the Sugarland Mobile Home Park in Clewiston, Fla., Monday, Oct. 24, 2005. Hurricane Wilma left a wide, messy swath of damage Monday as it sped across Florida with winds of more than 100 mph, shattering skyscraper windows, peeling off roofs and knocking out power to more than 6 million people from Key West to Daytona Beach. (AP Photo/Luis Alvarez)
10. Hurricane Michael, 2018
UpdatedTotal cost of damages: $25.5 billion
Storm category: 5
Deaths attributed to storm: 59
FILE - In this Oct. 12, 2018, file photo, debris from Hurricane Michael is scattered over Mexico Beach, Fla. Hurricane Michael's impact is one the top stories in Florida in 2018. (AP Photo/Gerald Herbert, File)
Photos: Gulf Coast braces for possible tandem hurricanes
Tropical Weather
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People line up to enter retail chain Costco to buy provisions in New Orleans, Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
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Mike Bartholemey places extra blocks under his recently dry docked shrimp boat, out of concern for strong winds, in Empire, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
Tropical Weather
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Mike Bartholemey places extra blocks under his recently dry-docked shrimp boat, out of concern for strong winds, in Empire, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
Tropical Weather
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Mike Bartholemey places extra blocks under his recently dry docked shrimp boat, out of concern for strong winds, in Empire, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
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Robert Nguyen buys gas for his generator in Port Sulphur, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
Tropical Weather
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People line up to enter retail chain Costco to buy provisions in New Orleans, Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
Tropical Weather
Updated
Mike Bartholemey places extra blocks under his recently dry docked shrimp boat, out of concern for strong winds, in Empire, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
Tropical Weather
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Robert Nguyen buys gas for his generator in Port Sulphur, La., Sunday, Aug. 23, 2020, in advance of Hurricane Marco, expected to make landfall on the Southern Louisiana coast. (AP Photo/Gerald Herbert)
