Updated at 11:50 a.m. ET
Hurricane Laura will make landfall as a major hurricane, with winds of around 115 mph and a storm surge up to 11 feet, when it strikes near the Louisiana-Texas border late Wednesday or early Thursday, according to the National Hurricane Center.
Laura was declared a hurricane Tuesday morning, when a NOAA hurricane hunter aircraft detected maximum sustained winds of 75 mph as the storm's center was crossing into the Gulf of Mexico. It's expected to draw more power from the gulf's warm waters.
"Significant strengthening is forecast during the next 48 hours," NHC forecaster Eric Blake said in his advisory.
A hurricane warning is now in effect from San Luis Pass, Texas — just south of Galveston — to Intracoastal City, La., meaning hurricane conditions are expected somewhere within the warning area, likely within 36 hours.
The weather agency issued a storm surge warning for an even wider area, from San Luis Pass to the mouth of the Mississippi River.
"Historically, the storm surge is the leading cause of fatalities in these tropical systems," NHC Director Ken Graham said.
The first tropical-storm-force winds could reach the U.S. mainland Wednesday morning. Coastal water levels could also rise sharply long before the hurricane makes landfall.
"You have to get ready today," Graham told residents via Facebook Tuesday, in a late-morning update.
If the surge peaks at the same time as high tide, areas such as Sea Rim State Park, Texas, Sabine Lake and Calcasieu Lake could see water that is 9-13 feet deep, the hurricane center says.
The storm is currently moving west-northwest – and forecasters say its long westward trip across the Gulf will give it time to strengthen.
When the storm arrives, experts warn, the affected area could be much larger than the cones that appear on forecast maps: Laura is projecting tropical storm-force winds for 175 miles from its center, and it will bring huge amounts of rain to inland areas.
"There is a risk of life-threatening storm surge from San Luis Pass, Texas, to Ocean Springs, Mississippi, within the next 48 hours," the NHC says, describing a storm surge watch that is now in effect.
Laura is expected to become a Category 3 storm, which routinely cause "devastating damage" to homes, trees and infrastructure, according to the National Weather Service. Recent Category 3 storms include Harvey, which hit Texas in 2017, and Rita, which hit Louisiana in 2005.
People in the storm's path, some of whom have already seen heavy rain from Tropical Storm Marco, are preparing for Laura's arrival. To the relief of many people along the gulf shore, Marco fizzled out as it reached Louisiana's coastline. But that storm, which spent less than a day as a hurricane, was far smaller and less powerful than Laura.
"We're at halftime right now," said New Orleans Office of Homeland Security and Emergency Preparedness director Colin Arnold, according to member station WWNO. "It was kind of an uneventful first half, thankfully. We're all happy about that. But we still have a third and fourth quarter to go in this. And that's Laura. And that's Wednesday."
The Texas town of Port Arthur — home to the largest oil refinery in North America — is currently in the middle of Laura's projected path. Its home county, Jefferson, enacted a mandatory evacuation order on Tuesday, with exemptions for essential workers at the refinery and elsewhere.
"Please take extra precautions to pack up your home and family and finalize your plans," the Jefferson County Sheriff's Office told residents.
The governors of Texas and Louisiana have declared states of emergencies due to the looming storm; both also say their requests for President Trump to grant a federal emergency declaration have been approved.
Texas Gov. Greg Abbott has also ordered "more than 70 members with the Texas Army, Air National Guards, and Texas State Guard" to position themselves in areas where they can respond to emergencies when needed. The order also puts UH-60 Blackhawk and UH-72 Lakota helicopter crews on alert.
As they contend with the storm, emergency agencies and evacuation facilities will be restricted by capacity limits and other concerns brought about by the COVID-19 pandemic. Both Texas and Louisiana have had large outbreaks of the viral disease.
"The virus is not concerned that we have hurricanes coming," Louisiana Gov. John Bel Edwards said earlier this week. "So it's not going to take any time off, and neither can we."
"We always tell you that the first 72 hours are on you," Edwards said, urging people to prepare for a possible severe impact from the storm – and to expect a delay in getting help.
"You should be prepared to shelter in place, yourself and your family, for at least that long," the governor added. The use of large shelters, he said, would be a last resort.
Laura is predicted to remain a tropical storm for at least a day after making landfall, bringing intense rainfall of from 4-8 inches. Some isolated areas will see as much as 12 inches.
"The threat of widespread flash and urban flooding, along with small streams overflowing their banks, will be increasing Wednesday night into Thursday from far eastern Texas, across Louisiana, and Arkansas," the NHC says.
Over the weekend, Laura's remnants are predicted to spread rains into the middle-Mississippi, lower Ohio and Tennessee Valleys.
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