Hurricane Maria was rumbling toward the exposed Caribbean island of Puerto Rico as an angry, Category 5 storm after hammering Dominica, where the Prime Minister said his nation has lost all that "money can buy and replace".

Prime Minister Roosevelt Skerrit said the initial reports were "of widespread devastation" on Dominica. His said roofs of many homes, including his own official residence, had been torn off by Maria's howling winds. He was concerned that heavy rains would cause deadly mudslides in his mountainous country.

"I am honestly not preoccupied with physical damage at this time, because it is devastating. Indeed, mind boggling," he said in a Facebook post. "My focus now is in rescuing the trapped and securing medical assistance for the injured.

"We will need help, my friend, we will need help of all kinds."

Maria has been fluctuating between a Category 4 and Category 5 status — a major storm driving deadly wind, rain and storm surge. At 8am yesterday, Maria was a Category 5 storm with sustained winds of 160mph., the National Hurricane Center said.

AccuWeather senior meteorologist Rob Miller said Maria should make landfall over southeast Puerto Rico this morning, bisecting the island as a Category 5 storm.

"They were spared the worst of Irma, but their luck has run out," Mr Miller said.

It is still too early to determine whether the storm will impact the U.S. East Coast - and any threat would not be until early next week.

Mr Miller said, however, that the storm will most likely take a course similar to Hurricane Jose, which swept north and had only an indirect impact on the U.S. continental East Coast. Florida, he said, likely will be spared Maria's wrath.

The National Weather Service in Puerto Rico warned that "catastrophic winds" are expected from Maria beginning on Tuesday afternoon. "Locations may be uninhabitable for weeks or months." In addition, "major to record rains and flooding are expected to accompany Maria," the weather service said.

With Hurricane Mara just 200 miles off the coast, Puerto Rican Gov. Ricardo Rosselló warned citizens that this will be a storm unlike any other they’ve seen and urged them to seek shelter.

“This will be a very violent event for Puerto Rico,” he said. “These are going to be hard times. This will not be a comfortable 72 hours.”

Rescue teams will likely not be able to go out for the next 72 hours, so residents in flood-prone areas or in unsecure buildings should evacuate now, Mr Rosselló said.

“This is the biggest storm we’ve seen in a century,” he said. “We’re going to see a lot of damage, we’re going to have to rebuild, but right now let’s focus on saving lives.”

Mr Rosselló said the government has prepared hundreds of shelters capable of housing more than 100,000 evacuees if necessary.

First, however, Maria will storm past the U.S. Virgin Islands, already battered by Hurricane Irma. Maria should sweep to the south of St. Croix, close enough to blast the island with hurricane-force winds. Tiny St. John's could see sustained, tropical force winds with hurricane-level gusts, he said.

The storm's centre reached Dominica late Monday, pounding the mountainous island with strong winds and heavy rains.

“The winds are merciless! We shall survive by the grace of God,” Mr Skerrit wrote at the start of a series of Facebook posts. “My roof is gone. I am at the complete mercy of the hurricane. House is flooding.” He later said he was rescued.

Mr Skerrit said it was too early to determine the condition of the airport and seaports, but he said they probably would be inoperable for a few days.

"That is why I am eager now to solicit the support of friendly nations and organizations with helicopter services" so he can fly over his country and survey the damage.

The storm is moving west-northwest on a course that threatens islands already devastated by Hurricane Irma.

Meanwhile, Hurricane Jose's 75-mph sustained winds will continue to bring rip currents and rough surf to the U.S. East Coast over the next several days.

Tropical-storm warnings have been posted along the southeastern New England coast, including most of the Rhode Island and Massachusetts coastline.

"Coastlines from North Carolina to southern New England are in for a long period of rough surf and an increasing risk of beach erosion," Weather Underground meteorologist Bob Henson said. "If Jose were to make landfall, it could end up producing significant surge even as a post-tropical storm."

Jose will produce heavy rain as it passes near southern New England and the Mid-Atlantic on Tuesday and Wednesday, the hurricane centre said. Total accumulations of 3 to 5 inches of rain are expected.

* This article first appeared in our sister title USA Today