New Orleans, Louisiana - Heavy rains and strong winds hammered Louisiana early Thursday as Tropical Storm Francine moved inland, leaving many residents without power while floods threatened the state.

The storm weakened from a hurricane as it moved over land, forecasters said, but it still posed risks and a flash flood emergency was earlier issued for the city of New Orleans.

Local TV stations and footage on social media showed coastal towns battered by the storm, with some streets flooded and locals filling sandbags to protect property from floodwaters.

More than 370,000 customers across Louisiana were without power, according to monitoring website poweroutage.us.

Francine made landfall as a Category 2 hurricane on a five-level scale in Terrebonne Parish, on the southern edge of the state, at 5:00 PM local time, according to the National Hurricane Center (NHC).

Hours later Francine was downgraded to a tropical storm with sustained winds of 50 miles per hour, with three to six feet of storm surge, and up to a foot of rain in some parts of Louisiana, as well as areas of Mississippi, Alabama, and the Florida panhandle, the NHC added.

"This rainfall could lead to considerable flash, urban, and river flooding," the NHC said.

The National Weather Service's New Orleans office issued a flash flood emergency for the city and nearby districts known as parishes, while New Orleans Mayor LaToya Cantrell urged residents to shelter in place.

"You need to be inside right now. Time to hunker down," Cantrell said in a video posted on social media.

In the town of Houma, residents filled sandbags, stocked up on supplies and filled their cars with gas ahead of the storm's arrival.

"We're working hard to stay here as long as we can... to take care of our people," a gas station manager who gave her name as Alicia B. told AFP.

The NHC said the storm is expected to quickly weaken as it moves inland over Louisiana and neighboring Mississippi.

Louisiana Governor Jeff Landry has declared a state of emergency, and on Tuesday requested a federal emergency declaration from President Joe Biden, which he quickly approved.

The Louisiana National Guard said on X that its soldiers were fuelling up vehicles in preparation for the storm. On Tuesday, it said it was mobilizing helicopters, boats and supplies for evacuations and search and rescue.

Schools and universities around the state capital Baton Rouge were preemptively closed until Friday, according to a government website.

Curfews starting as early as 6:00 PM were issued for communities across the Louisiana capital region, local media reported.

The 2024 Atlantic hurricane season, which began on June 1 and will end November 30, was expected to be busy but has seen just three hurricanes so far, reportedly puzzling scientists.

Hurricane Beryl became the earliest highest-level Category 5 storm on record after it formed in late June and plowed through the Caribbean, eventually hitting Texas and Louisiana, with dozens of deaths reported in its wake.

Scientists say climate change likely plays a role in the rapid intensification of storms, because there is more energy in a warmer ocean for them to feed on.