Hurricane Fiona makes landfall in Dominican Republic after knocking out power in Puerto Rico

Hurricane Fiona made landfall in the Dominican Republic early Monday after slamming Puerto Rico with heavy rain, life-threatening flooding and an islandwide power outage.

The Category 1 storm came ashore near Boca de Yuma at 3:30 a.m. with maximum sustained winds of 90 mph, the National Hurricane Center said.

As the storm is moving slowly to the northwest, it is still dropping flooding rain on Puerto Rico, where more than 1.4 million people are without power.

Officials said at least one person in Puerto Rico has died.

So far, at least one death has been reported in the heavily-damaged city of Basse-Terre, the capitol of the French territory of Guadeloupe, the vice president of the territory's environmental agency said Sunday.

The hurricane made landfall on the southwestern coast of Puerto Rico Sunday afternoon, bearing down on the island with severe winds of up to 75 miles per hour and bringing 6-24 inches of rain to some areas by the end of the day, according to the National Weather Service.

Fiona will continue to pummel Puerto Rico and eastern portions of the Dominican Republic into Monday. Eastern areas of the Dominican Republic may also see flooding as well as mudslides and landslides in higher areas, according to the hurricane center. Fiona could bring a total of up to 30 inches of rainfall to Puerto Rico and up to 12 inches to eastern and northern Dominican Republic.

The hurricane is forecast to build strength once it passes over the Dominican Republic and is expected to move towards Turks and Caicos and the Bahamas on Monday and Tuesday, according to the National Hurricane Center. The Turks and Caicos are under a hurricane warning and southern Bahamas are under a tropical storm watch.

LUMA Energy, the main power utility in Puerto Rico, said in a statement Sunday it could be days before power is restored, adding "several transmission line outages" are contributing to the blackout. The process will be done "gradually," Governor Pedro Pierluisi said in a Facebook post.

The website PowerOutage.us reported the entire island was without power, early Monday morning, adding LUMA had "reenergized some circuits, however there is limited information, and no numbers on how many customers have been restored."

Power outages have become a familiar crisis for many who live in Puerto Rico. Just five months ago, residents experienced another islandwide blackout after a fire broke out in a power plant.

Some parts of the island still bear the scars of Hurricane Maria, which devastated Puerto Rico almost exactly five years ago. After Hurricane Maria inflicted catastrophic damage to the territory's infrastructure, it took almost a year for power to be restored across the island.

Samuel Rivera and his mother Lourdes Rodriguez lived without power for about a year after Maria struck, Rivera told CNN's Layla Santiago. On Sunday morning, they lost power once again, conjuring up similar fears to those they had five years ago.

They said they are also concerned a nearby river may overflow and the trees surrounding their home may be felled by the powerful winds.

Life-threatening flooding tears through Puerto Rico

As Hurricane Fiona made landfall Sunday, most of Puerto Rico was under a flash flood warning in anticipation of the overwhelming downpour. The National Weather Service in San Juan warned of "catastrophic" and life-threatening flood conditions.

One video of the dangerous flooding shows the rushing waters easily wipe away a bridge, carrying its structure downstream. Another taken by Samuel De Jesús depicts a scene in the city of Arecibo as the rain falls in sheets, adding to the quickly-moving waters overtaking large construction vehicles and entire trees.

Many rivers on the eastern side of the island were in moderate to major flood stages Sunday afternoon, including one southeastern river which rose over 12 feet in less than 7 hours. By Sunday night, the National Weather Service also issued flash flood warnings across southern parts of central Puerto Rico.

In response to the risk Puerto Rico faced, President Joe Biden approved an emergency declaration early Sunday to provide federal assistance to disaster relief efforts.

More than 300 FEMA emergency workers were on the ground to respond to the crisis, the agency's Associate Administrator for Response and Recovery, Anne Bink, told CNN.

"Our heart goes out to the residents that again are going through another catastrophic event five years later," Bink said, nodding to the five-year anniversary of Hurricane Maria. This time, she said, FEMA plans to implement lessons learned from the 2017 crisis.

"We were much more prepared. We have four warehouses now strategically located throughout the island, which includes commodities, exponentially larger supplies than in the past," she said.

"We're proactively there -- and well ahead of any storm hitting -- to make sure that we are coordinating. And all of the planning efforts we undertake during those blue skies days can be brought to bear when the rain falls."

ABC News contributed to this report

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