NEW ORLEANS, United States (AP) — A fast-moving Zeta weakened to a tropical storm as it barrelled northeast Thursday morning after ripping through Louisiana and Mississippi where storm-weary residents were advised to stay indoors overnight while officials assessed the havoc the storm had wrought.

The storm raged onshore Wednesday afternoon in the small village of Cocodrie in Louisiana as a strong Category 2 and then moved swiftly across the New Orleans area and into neighbouring Mississippi, bringing with it both fierce winds and storm surge. There was heavy rain at times but since the storm was so fast-moving, rain related flooding wasn’t as much of a concern.

Zeta weakened over central Alabama but its strong winds continued across portions of the state and the Florida Panhandle. The storm was about 65 miles (104 kilometres) west northwest of Atlanta, Georgia, with maximum sustained winds of 60 mph (96 kph). Zeta is moving quickly toward the northeast at 39 mph (62 kph).

The storm killed at least one person, a 55-year-old man who a Louisiana coroner said was electrocuted by a downed power line in New Orleans, and officials said life-threatening conditions would last into Thursday.

Before dawn Thursday, about 1.8 million customers across Louisiana, Mississippi, Alabama and Georgia were without power, according to the website PowerOutage.us.

Waveland Mayor Mike Smith told WLOX-TV that his Mississippi Gulf Coast city, which was part of the area most heavily damaged by 2005’s Hurricane Katrina has maybe taken the worst hit since then from Zeta.

“We’re going to see a whole lot of damage in the morning,” Smith said. Among the many trees blown down was one that fell on Smith’s own house. “It was my next-door neighbour’s and he wanted to give it to me, apparently,” Smith said.

In Louisiana, Governor John Bel Edwards was expected Thursday to tour the coastal regions hardest hit by the storm. During a radio interview Wednesday evening, Edwards said the wind had caused extensive structural damage. And as neighbours and church groups started reaching out to help those affected, he also highlighted the need to protect against the coronavirus at the same time.

“Offer the help but do it with a mask on,” he said.

Much of New Orleans and the surrounding area was without power Wednesday night. The storm packed a punch as it whipped through the city. Signs outside bars and restaurants swayed back and forth in the wind and palm trees along Canal Street whipped furiously. Officials said a person was hospitalised with minor injuries after a structure collapsed.

More than 200 trees were reported down in the city. Echoing a plea made by officials across the Gulf Coast in the dark hours after the storm passed, New Orleans Mayor LaToya Cantrell implored residents to stay home and let city officials assess the damage.

“Although we have made it through, we have been damaged, we have been hit,” she said.

Along coastal Louisiana, there were reports of some trailers flipped over, a gas station destroyed, and downed power lines and trees.

Zeta had top sustained winds of 110 mph (177 kph) as a Category 2 hurricane at landfall and is the 27th named storm of a historically busy Atlantic hurricane season — with over a month left to go. It set a new record as the 11th named storm to make landfall in the continental US in a single season, well beyond the nine storms that hit in 1916.

Zeta weakened to a Category 1 hurricane with winds of 90 mph (144 kph) as it moved into southern Mississippi a few hours after landfall.