Hurricane Ida Strengthens as It Heads Toward Louisiana
 

8/28

Hurricane Ida strengthened Friday as it barreled toward Louisiana, with forecasters projecting it could strike land as a Category-4 storm and New Orleans ordering residents living outside the city’s levee system to evacuate.

Forecasts show Hurricane Ida’s winds potentially reaching as high as 140 miles an hour over the next two days as it moves over the open waters of the Gulf of Mexico before making landfall in Louisiana on Sunday.

“We do have a major storm heading our way,” said New Orleans Mayor LaToya Cantrell. “We are activating every single resource at our disposal so we are prepared to respond.”

The National Hurricane Center issued a hurricane watch for New Orleans, Lake Pontchartrain, Lake Maurepas in Louisiana and along the Gulf Coast from Cameron, La., through Mississippi to the border of Alabama. A hurricane warning was also in effect for the western Cuba provinces of Pinar del Rio and Artemisa, and the Isle of Youth, where the hurricane made landfall Friday afternoon with sustained winds of 75 mph.

If the storm makes landfall in Louisiana Sunday, it will arrive exactly 16 years after Hurricane Katrina devastated New Orleans. “We know that Aug. 29 is a very critical date in our city’s history and in all of our collective memories,” said Collin Arnold, director of the New Orleans Office of Homeland Security and Emergency Preparedness. “But that date has also taught us to be ready to be resilient, and that’s what we’re going to do together.”

Since Katrina, a $14.5 billion flood protection system—flood walls, levees, canals and barriers constructed by the U.S. Army Corps of Engineers—has helped bolster storm defenses around New Orleans.

Officials with the Flood Protection Authority East said they closed 24 land-based gates across the flood-protection system Thursday in anticipation of the storm, and plan to close another 27 gates Friday. The remaining 50 will be closed by Saturday, said Kelli Chandler, regional director of the Flood Protection Authority-East.

“We are confident it will perform as designed,” Ms. Chandler said.

Mandatory evacuation orders were issued for residents living outside of the levee system in Irish Bayou, Venetian Isles and Lake Catherine. New Orleans officials also called for voluntary evacuation across Orleans Parish. The National Hurricane Center said storm surge may possibly top levees outside of the Hurricane and Storm Damage Risk Reduction System.

Louisiana Gov. John Bel Edwards has declared a state of emergency and warned Louisianans to plan for flash flooding, heavy rains and power outages.

“Hurricane Ida is rapidly intensifying and the situation is changing, it seems by the hour,” the Democrat said Friday. “By nightfall tomorrow night, you need to be where you intend to ride out the storm.”

Mr. Edwards said he had authorized the Louisiana National Guard to be available to respond. President Biden, meanwhile, has approved a federal emergency declaration.

At Mike’s Hardware & Supply in the Gentilly neighborhood of New Orleans, people loaded up on flashlights, batteries and sealants for last-minute home repairs. The store sold out of gas cans earlier in the day.

“I’m having flashbacks to Katrina,” said co-owner Rob LaFleur, 47 years old, who said he spent eight days stranded in the store’s upstairs apartment during that storm. He said Ida’s projected landfall on the 16th anniversary of Katrina made him “very anxious.”

Still, Mr. LaFleur plans to stay through the storm—possibly in that same upstairs apartment—to look after the business and family home. “I’m just hardheaded,” he joked. “I was an Eagle Scout and a Marine.”

Forecasters warned Ida could bring storm surges as high as 15 feet above ground along parts of the Louisiana coast and as much as 20 inches of rain in some areas of southeast Louisiana and the coasts of Mississippi and Alabama.

“There’s a lot of water and very few places for it to go,” said Joel Cline, tropical program coordinator for the National Weather Service. “Clearly, people need to prepare.”

Ida’s projected path also made it a threat to the vast oil refining and petrochemical complex situated along the U.S. Gulf Coast, though the storm’s more easterly track Friday suggested it would miss the heart of those operations in Texas and along the Texas-Louisiana border.

The storm was also affecting offshore production platforms in the Gulf of Mexico, which account for roughly 17% of the nation’s oil production and around 5% of its natural gas output.

Refineries in Louisiana and Mississippi had started to reduce or halt output, which will lead to some gasoline delivery delays to Florida,

Projections have Ida sweeping through the bulk of U.S. offshore oil production, located south and southeast of Louisiana, said Andy Lipow, president of Houston-based consulting firm Lipow Oil Associates. He expects as much as 90% of offshore oil output to close ahead of the storm.

“Hurricane Ida is showing up probably in the worst possible location for oil production,” Mr. Lipow said.

By Friday afternoon, offshore producers had shut down 59% of oil output and 49% of natural gas production in the U.S. Gulf of Mexico

The center of the storm was approaching western Cuba Friday evening, with maximum sustained winds of 75 mph. A tropical-storm warning was in effect for parts of Cuba. National Hurricane Center forecasters warned of heavy rains, flash flooding and mudslides in Jamaica, the Cayman Islands, western Cuba and the Isle of Youth.

The National Hurricane Center said Ida was expected to strengthen after it passes over western Cuba, as the storm moves through the open waters of the Gulf of Mexico late Friday and Saturday.

—Talal Ansari, Collin Eaton, Rachel Wolfe and Jennifer Hiller contributed to this article.

Write to Jennifer Calfas at jennifer.calfas@wsj.com