The powerful storm, which made landfall Monday night, has since been downgraded to a Category 4 with sustained winds of 155 mph. After it passes over Dominica it is on course to score a direct hit on the US territory of Puerto Rico -- the first hurricane of its strength to do so in 85 years.
"We're just waiting for daybreak to do an assessment of the damage," Dominica Prime Minister Roosevelt Skerrit told CNN's Rosemary Church.
"Our first order of business will be search and rescue to ensure we can account for every single citizen and residents who were on the island during this really devastating hurricane."
A statement from the National Hurricane Center (NHC) said that its record-topping winds reached 160 miles per hour when it hit the island nation. In an update the Center said that reports "indicate significant damage to structures has occurred in Dominica."
Maria made landfall on Dominica late Monday, coming ashore at 9:15 p.m. ET. It was so powerful that it tore the roof off the Prime Minister's residence.
"Personally I was affected," Skerrit said. "The roof of the residence caved in because of the strength of the wind. But I was taken to safe ground by ... police officers, thank God.
"This hurricane stayed in the country for a very, very long time and (was) just unrelenting. I don't think there were very many roofs which would survive the hurricane."
In a Facebook post he added: "So far we have lost all what money can buy and replace.
"My greatest fear for the morning is that we will wake to news of serious physical injury and possible deaths as a result of likely landslides triggered by persistent rains."
The storm will continue moving toward Puerto Rico and the Virgin Islands as a strong Category 4 or a Category 5 and is not expected to diminish in strength.
After Dominica, Puerto Rico is in Maria's sights. It is moving toward the island as an "extremely dangerous major hurricane, and a hurricane warning has been issued for that island," the hurricane center said.
Puerto Rico's governor, Ricardo Rosselló, has declared a state of emergency ahead of that landfall, which will likely happen Wednesday.
A hurricane warning from the NHC remains in effect for Guadeloupe, Dominica, St. Kitts, Nevis, and Montserrat, the US and British Virgin Islands as well as Puerto Rico, Culebra, and Vieques.
US President Donald Trump issued an emergency declaration for the US territory for federal assistance to augment the territory's storm-response initiatives.
The ferocity of Maria bears striking similarities to Hurricane Andrew, the Category 5 hurricane which hit the Bahamas and Florida in 1992, says CNN meterologist Pedram Javaheri. Both storms are compact, and Maria's wind speed comes close to that of Hurricane Andrew -- 165 mph -- when it hit southern Florida.
Bracing for impact
Hours before Maria's expected landfall on Dominica -- and just over week after the island was brushed by Irma -- Skerrit urged residents to take any belongings that could become dangerous projectiles indoors.
"The next few hours should be placed on cleaning up around the house and on your properties rather than stockpiling weeks of foods and other supplies," Skerrit said in a televised speech.
"This is not a system that will linger very long. Therefore, the goal must not be on stockpiling supplies but on mitigating damage caused by flying objects."
Puerto Rico on alert
Puerto Rico sheltered many of the evacuees who fled Hurricane Irma's wrath in other Caribbean islands. Now those evacuees and native Puerto Ricans are bracing for another powerful hurricane.
Rosselló ordered evacuations ahead of deteriorating conditions, telling CNN that extensive preparations had been made to mitigate Maria's potential impact.
"We're as ready as we can be," he told CNN's Don Lemon.
"This sort of event is a very dangerous event, high winds, a slow storm and a lot of rainfall. And this coming just about two weeks after Irma skirted off the northeast of Puerto Rico.
"We've made preparations... we've focused on really the only thing that matters right now, which is making sure people are safe. We have 500 shelters, (we're) moving people to those shelters and hopefully weathering the storm so we can rebuild Puerto Rico.
Calling its potential impact "catastrophic," Rosselló said that the island was expected to experience tropical storm force winds for about two and a half days and sustained high level hurricane winds for "the better part of a day."
"We expect to feel storm winds, tropical storm winds, since Tuesday up until late on Thursday. That's about two-and-a-half days of tropical storm winds, and on Wednesday we will feel the brunt -- all of the island will feel the brunt of sustained category four or five winds, Rosselló said.
"This is an event that will be damaging to the infrastructure, that will be catastrophic, and our main focus -- our only focus right now -- should be to make sure we save lives."
If Maria strikes the island as forecast, it will be "more dangerous than Hugo and Georges," he said.
Hurricane Hugo killed five people in Puerto Rico
in 1989, and Hurricane Georges caused more than $1.7 billion in damage to the island
In Salinas, a city on the island's southern coast where the storm is expected to hit hard, CNN saw dozens of people queuing for water and essentials ahead of the hurricane's anticipated impact.
Restauranteur Juan Miguel Gonzalez told CNN he was "worried" about the storm's impact. "Not about material stuff, rather the people," he said.
His staff were working to prepare the waterfront property for Maria's arrival and the 39-year-old said that he would return tomorrow to make sure that it was secure.
The Puerto Rico Convention Center in the capital San Juan to the north, which is still housing Hurricane Irma evacuees from other Caribbean islands, is preparing to accept thousands of residents as the brunt of the storm is felt.
Hurricane and tropical storm warnings
The storm will affect parts of the Leeward Islands and the British and US Virgin Islands for next couple of days, the center said.
Other Leeward Islands are now under hurricane warnings, including Guadeloupe, Dominica, St. Kitts, Nevis and Montserrat. the US Virgin Islands and the British Virgin Islands are under warnings.
Trump issued an emergency declaration for the US Virgin Islands.
There are tropical storm warnings in effect for Martinique, Antigua and Barbuda, Saba and St. Eustatius, St. Martin, Anguilla and St. Lucia.
The government of the Dominican Republic has issued a hurricane watch from Isla Saona to Puerto Plata, and a tropical storm watch west of Puerto Plata to the northern Dominican Republic-Haiti border.
The British Foreign Office said more than 1,300 troops are in the region, on affected islands or nearby locations, ready to help after Maria goes by. One military team has been deployed to the British Virgin Islands.
A British military reconnaissance team is on standby to go to Montserrat and assess needs, the office said. The HMS Ocean is set to arrive in the area at week's end with 60 tons of government supplies.
Another hurricane, Jose, is also churning in the Atlantic and has spawned tropical storm warnings for part of the US East Coast.
While forecasters don't anticipate Jose making landfall in the US, it's still expected to cause "dangerous surf and rip currents" along the East Coast in the next few days, the hurricane center said.