NEWS ORLEANS (ABC) - Tropical Storm Nate is dumping heavy amounts of rain as it weakens and moves northward and away from the U.S. Gulf Coast.
The National Hurricane Center in Miami says Nate's maximum sustained winds have decreased to near 45 mph (75 kph) with higher gusts. The storm is expected to continue to rapidly weaken as it moves farther inland across the Deep South, Tennessee Valley and central Appalachian mountains. Through Monday, those areas can expect at least 3 to 6 inches of rain.
The hurricane center discontinued its storm surge warning for the area west of the Mississippi-Alabama border. A tropical storm warning was discontinued for the area west of the Alabama-Florida border.
Hurricane Nate -- which is threatening to bring a life-threatening storm surge to the Gulf Coast -- made landfall near the mouth of the Mississippi River on the southeastern Louisiana coast Saturday evening.
Concerns about the Category 1 hurricane prompted officials in Louisiana, Mississippi, Alabama and Florida to declare states of emergency, order evacuations and issue curfews.
Maximum flooding of 7 to 11 feet above ground level is expected in parts of southeast Louisiana and along the Mississippi coast, the National Hurricane Center said. A storm surge warning is in effect from Grand Isle, Louisiana, to the Okaloosa/Walton county line in Florida.
As of 7 p.m. CT, the storm's center was about 100 miles south of Biloxi, Mississippi, moving north at 20 mph with sustained winds of 85 mph, and was expected to make landfall along the Mississippi coast in several hours.
The highest storm surge is expected Saturday night along the Mississippi coast and southeastern Louisiana coast. The water is forecast to recede Sunday morning as the storm quickly moves inland.
As Nate races inland Sunday, it's expected to rapidly weaken and should barely be a tropical storm by Sunday night, weakening further to a tropical depression by early Monday morning. But heavy rain and flash flooding will still be a concern as the storm roars ashore and moves inland, said ABC News meteorologist Daniel Manzo.
On Thursday, Nate brought deadly mudslides and flash floods to Central America as it traversed the western Caribbean Sea as a tropical storm. According to The Associated Press, 22 people were killed, including 15 in Nicaragua and seven in Costa Rica. Costa Rican officials said 15 people were missing as well.
Nate strengthened into a Category 1 hurricane late Friday night.
The governors of Louisiana, Mississippi and Alabama all issued stern warnings to residents ahead of the storm's expected landfall on the southeastern U.S. coastline.
Louisiana Gov. John Bel Edwards declared a state of emergency on Thursday and warned residents to prepare for heavy rain, storm surge and high winds.
"No one should take this storm lightly," Edwards said at a press conference Friday. "We do want people to be very, very cautious and to not take this storm for granted."
In New Orleans, where a citywide curfew will be in effect from 7 p.m. Saturday to 7 a.m. Sunday, Mayor Mitch Landrieu has declared a state of emergency and is urging residents to stay off the streets.
The city is under a storm surge warning and Landrieu said some areas outside of the levee protection system could see a 7-to-11-foot storm surge.
Landrieu ordered a mandatory evacuation for the communities of Venetian Isles, Lake Catherine and Irish Bayou.
One man who lives on Venetian Isles told The Associated Press that his wife evacuated to a hotel, but he is staying behind because an elderly neighbor refused to leave.
"I know it sounds insane, but he has bad legs and he doesn't have anybody who can get to him," Gabriel Black told the AP.
The mayor also warned that with wind gusts potentially up to 80 mph, the city could see significant power outages.
In Mississippi, Gov. Phil Bryant on Friday declared a state of emergency in several southern counties in preparation for the storm.
"If you are in an area that has flooded, I would recommend you evacuate that area until the storm has ended and the water has receded for your own personal safety and for the safety of the first responders that will be responding in the event you are trapped," Bryant said at a press conference Friday.
All Mississippi coast casinos have closed, according to the Mississippi Gaming Commission. Some hotels will remain open to guests, while others will close to guests, according to the Mississippi Emergency Management Agency.
Alabama Gov. Kay Ivey issued a statewide state of emergency that went into effect Friday morning. Ivey said that while the coast will experience the worst of the storm, Birmingham could experience strong winds and rain.
"It has become clear that Alabama, especially on our coast will experience some of the worst conditions from this storm," Ivey said at a press conference Friday. "Alabamans, you must prepare and be vigilant. This is serious business."
Curfews are set for Saturday night to Sunday morning in Gulf Shore, Alabama, and Orange Beach, Alabama.
Florida Gov. Rick Scott also declared a state of emergency in some counties.
Meanwhile, the Bureau of Safety and Environmental Enforcement said dozens of offshore oil and gas platforms as well as drilling rigs in the Gulf of Mexico have been evacuated.