First up: Tropical Storm Marco, which is expected to intensify after a Category 1 hurricane Sunday before making landfall on the Louisiana coast Monday afternoon.
“This is the more serious threat because it will make landfall first,” CNN meteorologist Allison Chinchar said.
Then there’s Tropical Storm Laura, which is also expected to intensify after a hurricane before making it to the U.S. late Wednesday or early Thursday – either on or off the coast of Louisiana.
Parts of the Gulf Coast will be flooded with both sea and air.
Life-threatening storm surge
The National Hurricane Center warned Monday of “life-threatening storm surge” when Marco hurled walls of water to the Gulf Coast.
Storm surges are expected to be 4 to 6 feet high from central Louisiana east to Biloxi, Mississippi. That area includes New Orleans.
The rest of the Louisiana coast, the rest of the Mississippi coast and the Alabama Gulf coast are expected to see 2-to-4-foot storm surges.
“Eventually, the big concern will be storm surge,” Chinchar said.
Torrential rains will also flood the coast
Marco is expected to “bring a tremendous amount of rain, not just to Louisiana, but areas of Mississippi, Alabama and even Florida,” Chinchar said.
New Orleans will be flooded earlier this week with several inches of rain.
“Then you have Laura making her way into the Gulf, shortly after Marco makes a landfall,” Chinchar said.
“Even on Monday and Tuesday, Key West, Miami – you’ll get some of Laura’s outer bands, producing very heavy rain and heavy wind,” she said.
As of Sunday, “Laura is over the Dominican Republic, dumping a huge amount of rain there.”
By the time Laura reaches the U.S. coast, it is expected to be a Category 2 hurricane – maximum sustained winds of at least 96 mph. Laura is expected to affect many of the same areas that will be affected by Marco.
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