New Orleans, Gulf Coast brace, prepare for Hurricane Nate

Hurricane Nate barreled toward the US Gulf Coast overnight with slashing rain and powerful winds, and the storm raced steadily and rapidly toward a possible landfall early Sunday, with its center coming ashore just east of New Orleans.

National Hurricane Center says strengthening Nate expected to be a Category 2 hurricane at landfall on Gulf Coast .

Packing 80 miles per hour winds and moving northwest at 22 mph, the Category 1 hurricane is 345 miles south-southeast of the mouth of the Mississippi River, in the southern Gulf of Mexico, the National Hurricane Center said in its latest advisory, at 5 a.m. ET Saturday morning.

"A hurricane warning is in effect for portions of the northern Gulf Coast from Louisiana to Alabama, and preparations to protect life and property should be rushed to completion in these areas," the hurricane center said. "Life-threatening storm surge flooding is likely along portions of the northern Gulf Coast."

CNN meteorologist Jennifer Varian said the storm is expected to reach landfall around 1 a.m. with winds at 90 miles per hour. "Once it hits land it looks like its going to be very quick to move out of the area and then weaken," she said.

Nate could drop 3 to 6 inches of rain, with 10 inches possible in some areas, from the central Gulf Coast north through the Deep South, the eastern Tennessee valley and the southern Appalachians through the weekend into Monday, possibly spawning flash floods, the hurricane center said.

Hurricane warnings have been issued along the northern Gulf Coast from New Orleans to Lake Pontchartrain and Grand Isle, Louisiana, eastward to the Alabama-Florida border. A storm surge warning is in effect for Morgan City, Louisiana to the Okaloosa/Walton County line in Florida.

New Orleans braces for impact

Nate could be the third hurricane to hit the US mainland in six weeks. Hurricanes Harvey and Irma tore through some coastal states killing dozens and destroying thousands of properties.

The storm has already left a path of devastation in Central America. At least 24 people were killed in Costa Rica, Nicaragua and Honduras on Thursday. Hundreds were rescued from floodwaters and mudslides. Many lost power and running water.

First responders, sewer workers and residents are preparing for flooding in New Orleans, which was devastated 12 years ago by Hurricane Katrina. The storm is expected to make landfall in the close vicinity of New Orleans by early Sunday.

On Friday, New Orleans Mayor Mitch Landrieu ordered a mandatory evacuation of the Venetian Isles, Lake Catherine and Irish Bayou areas of the city after having already declared a state of emergency Thursday.

In preparation for overnight flooding, Landrieu also announced a mandatory curfew that will go into effect Saturday at 6 p.m. and end Sunday morning.

He urged people who live "outside the city's levee protection system or in low-lying area" to seek higher ground as much of the city lies below sea level.

Residents have been wary since the city's unique drainage system experienced critical deficiencies during heavy summer rainstorms, leading to the flooding of several hundred properties.

Some of the city's drainage pumps and some turbines that help power the city's oldest pump stations were offline earlier this week, city records showed.

Gov. John Bel Edwards declared a state of emergency for all of Louisiana and mobilized 1,300 National Guard troops ahead of the storm.

"We are taking the potential impacts of Tropical Storm Nate seriously and mobilizing all of the state's emergency preparedness and response mechanisms for a full readiness should this storm severely impact our state," Edwards said.

Airport, port closings

Nate's projected landfall will have an impact on several flights and an important port along the Gulf Coast.

In Florida, the Pensacola International Airport will cease operations Saturday night and will remain closed throughout Sunday due to the storm, airport officials said.

In Alabama, where Gov. Kay Ivey signed a statewide emergency declaration Friday, the Mobile Regional Airport will also be closing Saturday afternoon and reopening Sunday at noon, an airport official said.

Mobile officials were checking storm drains for debris, taking measures to avert power outages and deploying critical equipment. Coastal Alabama officials said they are closing beaches and ordered voluntary evacuations in parts of the coast.

Meanwhile in Mississippi, the Air Force Reserve's 403rd Wing relocated their aircraft to Texas and Arkansas. The Kessler Air Force Base in Biloxi was not evacuated, officials said.

"We are moving aircraft as a precautionary measure ahead of Tropical Storm Nate, and so we can continue the mission," said Col. Jennie R. Johnson in a statement.

The Port of Mobile closed Saturday because of Nate and that keeps the Carnival Fantasy cruise ship "from making its scheduled call in Mobile" on Sunday, the Mobile Alabama Cruise Terminal said.

"We recommend passengers stay tuned to communications from Carnival and also check their website for itinerary updates," the terminal said. CNN is reaching out to Carnival for a statement.