Tropical storm loses strength after causing $2.5bn destruction in US

Tropical Storm Nate is rapidly weakening over the southern US even as flooding from storm surges continues along the Mississippi-Alabama coast.

Thousands were without power early on Sunday, and storm-related losses were estimated to reach about $2.5bn.

Nate’s top winds fell to 70kph from 100kph in just three hours as it moved north-northeast, the US National Hurricane Centre said. The storm made its final landfall near Biloxi, Mississippi, as a category 1 hurricane early on Sunday.

“This morning’s after-landfall estimate is $2.5bn. That shouldn’t change much going forward,” said Chuck Watson, a disaster modeller in Georgia.

“The intensity crashed at landfall; the left side collapsed.” The lack of power on the left, or west, side of the storm meant New Orleans was spared Nate’s flooding rains. That lowered damage estimates, which had been as high as $4bn when the storm was gaining strength in the Gulf of Mexico on Saturday, Watson said.

Flooding and landslides caused by Nate earlier killed more than 20 people across Central America.

The region’s oil and natural gas operators mostly stopped production ahead of Nate’s arrival. About 92% of US Gulf oil production and 77% of natural gas output was taken off line, the Bureau of Safety and Environmental Enforcement said.

The US Coast Guard suspended marine traffic and closed ports on Saturday, while Magellan Midstream Partners reduced operations at its petroleum storage terminal in Marrero, Louisiana. A Colonial Pipeline spokeswoman said the storm had had “no impact” on its operations.

At least 67,000 customers were without power in Alabama and Mississippi, with the majority of those in Mobile, according to local utilities.

The storm would continue to lose power as it moved north and was eventually absorbed by another weather system moving across the US, said Rob Miller, a meteorologist.

“Winds are less of a factor now across Alabama and the southeast states. It is mostly transitioning into a rain threat.”

It is possible that rains from Nate, along with a frontal system moving across the US, could combine to bring heavy rain into Pennsylvania, New York and New Jersey by Monday.

In the next five days, nearly 230mm of rain could fall across parts of the south Appalachian Mountains, while a swath from eastern Ohio through upstate New York into northern New England could get close to 75mm, the US Weather Prediction Centre said.

All told, 14 storms have formed across the Atlantic this season, killing hundreds in the US, Mexico and the Caribbean and causing an estimated $300bn in damage. Including Nate, six storms had hit the US so far in 2017, said Dennis Feltgen, a spokesman for the hurricane centre.