BILOXI, Miss. — This year’s crushing hurricanes have submerged Houston, wrecked the Florida Keys and decimated Puerto Rico, but spared the central Gulf Coast — at least until now.
Hurricane Nate, the fourth hurricane to lash the United States in just over six weeks, gained strength on Saturday and made landfall in southeast Louisiana, near the mouth of the Mississippi River, as a Category 1 system.
The governors of Alabama, Florida, Louisiana and Mississippi declared states of emergency ahead of the storm, and counties along the coast issued curfews and ordered evacuations.
“Sooner or later, living here, you’re going to get hit,” said Rich Hazen, 52, of Diamondhead, Miss., as he stopped for a coffee, having already prepared his generator, cleared his yard and gathered drinking water ahead of the storm.
After amassing power in the Gulf, the hurricane raced toward land and was lashing coastal cities with rain by late afternoon. Some areas were expected to receive 6 to 10 inches of rainfall as the storm passed through, although forecasters said that a “life-threatening” storm surge, or an abnormal rise in water levels of up to several feet, as well as wind were likely to cause the biggest problems.
Gov. John Bel Edwards of Louisiana said on Saturday afternoon that Nate was moving at “an extremely fast rate” of 26 miles an hour, which he said was “almost unheard-of for a storm of this type.”
Even though its speed would limit the amount of time it could deluge any single place, Mr. Edwards said, “this is a very dangerous storm nonetheless.”
“It has proven to be very deadly in Honduras and Nicaragua and that area,” Mr. Edwards said. “We have to make sure we are not taking it lightly.” At least 22 storm-related deaths have been reported in Central America.
The hurricane hit the same stretch of coast that is, in many ways, still recovering from Hurricane Katrina in 2005. At the 17th Street Canal between New Orleans and Metairie, La., workers from the Army Corps of Engineers lowered a set of enormous gates at the mouth of the canal. On Friday, divers checked the beds that the gates rest on to make sure that they would be able to close.
In 2005, there were no gates there or at the three other rainwater drainage canals in New Orleans. Katrina’s surge pushed water from Lake Pontchartrain deep into the canals. When levees along those canals breached, much of the city was inundated, and stayed underwater for weeks, until the breaches could be closed and the neighborhoods pumped dry. The corps later acknowledged the hurricane protection system it built was “a system in name only.”
Now the corps is building permanent pumping stations at the very end of these canals. Until then, a structure of gates and temporary pumps has been built to protect nearby neighborhoods.
Mayor Mitch Landrieu of New Orleans said at a news conference Saturday that he expected the city’s pump system to function effectively. Of the 120 pumps, 108 were working. “We have plenty enough to deal with the potential rain,” he said. “Everything that we can see, we think we can handle.”
The city could be without power for as long as a week, officials said. As for the question of how protective the city’s $14.6 billion system of levees, flood walls and gates would be against Nate, Mr. Landrieu expressed cautious optimism. “There is limited or no risk for storm surge in the city of New Orleans,” he added.
In the afternoon, as Nate’s outer bands hit New Orleans, rain pounded the streets, pushed by heavy gusts. Pedestrians took off running or huddled under overhangs.
Nia Johnson, 23, who lives on Alvar Street a few dozen blocks from the Mississippi River, said that she and her family had planned to pile into the car and drive to Lafayette, La., because the streets of her area “always flood.” The power would almost certainly go out because of the high winds, she said, leaving them unable to cook for days.
Many of the larger chain establishments in the French Quarter had closed. But along Bourbon Street, the daiquiri and pizza-slice joints were open, and music spilled out of bars like the Beach, where customers wearing fleur-de-lis-covered ponchos were drinking and watching college football.
Bridesmaids tried to stay dry in front of Arnaud’s restaurant, where a Rolls-Royce waited for the bride and groom. Around the corner, a wedding party was out on a second-floor balcony despite the splitting rain.
Farther east, in Biloxi, a casino city that lost 6,000 structures in Hurricane Katrina, officials urged residents to prepare for Nate as quickly as possible. The Mississippi Gaming Commission ordered all coastal casinos closed.
Vincent Creel, the public affairs manager in Biloxi, said Hurricanes Harvey and Irma, which passed west and east of the area, had served as stark reminders of a hurricane’s havoc.
“It’s been to the left, to the right, and now right to us,” Mr. Creel said.
In the coastal cities of Gulf Shores and Orange Beach, Ala., officials issued curfews and ordered mandatory evacuations in low-lying areas, including all beachfront condos and duplexes. Streets normally filled with traffic were desolate, drubbed by the rain, and beaches were empty except for whipping red flags. Gas stations ran out of fuel.
Just a few hours earlier, there had been an air of calm along the coast.
Merlin and Suzie DeCorte, of Metaire, La., stopped at the R & O restaurant with their son Jacob, 8, near the 17th Street Canal in New Orleans, all wearing Louisiana State University T-shirts.
“It didn’t seem like it was going to be that bad,” Ms. DeCorte said of the storm. They had more time, she said, to get away from the city if needed.
In Gulfport, La., Mr. Hazen and his wife, Dawn, were completing their errands with a decided sense of normalcy.
“Church hasn’t been canceled for this evening,” Ms. Hazen said.
“And Waffle House is still open,” Mr. Hazen said, citing the ever-reliable barometer of Southern disaster.
“If they close,” Ms. Hazen said, “then you know you’re in trouble.”
Jess Bidgood reported from Biloxi, Miss., and John Schwartz from New Orleans. Reporting was contributed by Katy Reckdahl and Amy Virshup from New Orleans, Kalyn Wolfe from Orange Beach, Ala., and Vivian Wang from New York.