Hurricane Fiona approaching a powerless Puerto Rico

Hurricane Fiona barreled toward Puerto Rico's coast, knocking out all power and threatening to cause "catastrophic flooding" in the US island territory.

The US National Hurricane Center (NHC) said on Sunday that the eye of the storm was approaching the southwest coast of Puerto Rico, and that "catastrophic flooding" was expected there and in the Dominican Republic, an island nation to the west.

Packing winds of 140 kilometres per hour, Fiona is forecast to strengthen further in the next 48 hours as it moves toward Puerto Rico and the Dominican Republic before heading north into the open waters of the Atlantic Ocean.

The National Weather Service's San Juan office also warned on Twitter of "life-threatening flash flooding of streams, highways and streets, as well as urban, low-lying and poorly drained areas."

The island lost power as Fiona neared Puerto Rico, Governor Pedro Pierluisi said in a statement posted on Twitter.

"Due to the effect of the hurricane, the electrical system is currently out of service," he said, adding that flooding has been reported in various parts of the island.

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State of emergency declared

The storm has already caused a fatality, with a man left dead when his house was swept away by flooding in the French overseas department of Guadeloupe, when Fiona was still classified as a tropical storm.

US President Joe Biden declared a state of emergency for Puerto Rico on Sunday as Fiona approached the island, authorising the Federal Emergency Management Agency to provide assistance.

Pierluisi told a news conference the previous day that "we are asking residents not to leave their homes and to go to shelters if they are in areas prone to landslides and flooding."

The island — which has suffered from major infrastructure problems for years — was hit by hurricanes Irma and Maria in 2017, devastating its electrical grid.

The grid was privatised in June 2021 in an effort to resolve the problem of blackouts, but the issue has persisted, and the entire island lost power earlier this year.

Power outages were hitting Puerto Rico even before the full force of Hurricane Fiona struck, with more than 388,000 people without electricity, according to tracking website poweroutage.us.

The former Spanish colony became a US territory in the late 19th century before gaining the status of associated free state in 1950.

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