Ernesto slams Puerto Rico with heavy rain and strong winds, causing mass power outages

Tropical Storm Ernesto pummeled Puerto Rico and the Virgin Islands early Wednesday, unleashing torrential rain and damaging winds that triggered urgent flash flood warnings as over a half million people lost power throughout the territory.

As of 8 a.m. ET, Ernesto was located 125 miles northwest of San Juan, Puerto Rico, with sustained winds of 70 mph, closing in on the 74 mph threshold for a hurricane, according to the National Hurricane Center . Forecasters say the storm is expected to develop into a hurricane Wednesday morning as it moves further into warm Atlantic waters.

The National Hurricane Center said both the U.S. and British Virgin Islands were likely to receive 4 to 6 inches of rain, and the total for southeastern Puerto Rico was forecast at 6 to 8 inches, with a maximum of 10. The heavy rain triggered a slew of flash flood warnings across Puerto Rico early Wednesday as wind gusts reached up to 86 mph.

Besides closing schools and asking the public to stay at home, officials in Puerto Rico – home to more than 3 million American citizens – activated the National Guard and opened shelters Tuesday. Flights at Luis Munoz Marin International Airport in San Juan, Puerto Rico, were canceled by their respective airlines .

On Tuesday, President Biden approved an emergency declaration for Puerto Rico, ordering the federal government to assist in local response efforts.

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Over half a million power outages reported in Puerto Rico

More than 600,000 utility customers were without power across Puerto Rico as Tropical Storm Ernesto slammed the U.S. territory with powerful winds and heavy rain.

Caguas, a major city in east-central Puerto Rico, had the most outages, with approximately 166,693 in the dark Wednesday morning, according to the website of Luma Energy , the operator of Puerto Rico’s power grid.

The next highest outage total, 123,976, was recorded in Ponce, a large city on Puerto Rico's southern coast, according to Luma Energy. In Carolina, a municipality east of San Juan, 115,852, outages were reported. San Juan had 58,195 houses and business in the dark Wednesday morning.

Luma Energy on Tuesday said it had coordinated with emergency contractors throughout Puerto Rico to respond to outages, and it encouraged customers to keep their contact information up to date so they can receive the latest announcements. Blackouts have been commonplace ever since Hurricane Maria destroyed Puerto Rico's power grid in 2017.

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Damaging wind gusts, flooding in Puerto Rico and the Virgin Islands

As Ernesto's pummeled Puerto Rico early Wednesday morning, officials issued under flash flood warnings as the national hurricane center reported damaging wind gusts.

By 7 a.m., between 2 and 6 inches of rain has fallen in parts of eastern Puerto Rico, and an additional 2 to 3 inches was projected. "Flash flooding is ongoing or expected to begin shortly," the weather service in San Juan said .

As rain totals climb, the Rio Grande de Loiza and its tributaries "continue to rise, and the flooding risk continues to increase," the weather service said, adding, "These rivers will likely overflow during the morning hours."

Meanwhile, Saint John and Saint Thomas in the U.S. Virgin Islands received between 3 and 5 inches of rain through Wednesday morning, leading the weather service to warn of the potential for "Life threatening flash flooding of creeks and streams, urban areas, highways, streets and underpasses."

According to the National Weather Service office in San Juan, an 86 mph wind gust was recorded in Culebra, a small island off the eastern coast of Puerto Rico. A National Weather Service crew in Ceiba County, in northeastern Puerto Rico, recorded a gust of 74 mph. Winds as high as 75 mph were recorded across the Virgin Islands, the weather service said.

Will Ernesto impact the US?

While Ernesto isn't expected to hit the mainland U.S., authorities have warned of potentially dangerous beach conditions — such as rip currents and rough surf — along the nation's Atlantic coast as the storm churns toward Bermuda.

The U.S. Coast Guard on Monday cautioned recreational boaters, fishermen, beachgoers, and water sports enthusiasts in the U.S. Virgin Islands and Puerto Rico to stay out of the water "due to deteriorating sea state conditions and dangerous rip currents associated with Tropical Storm Ernesto."

Forecasters said strong swells will begin to reach North Carolina beaches by Friday and advised beachgoers to be aware of the risks and dangers.

"The storm may be hundreds of miles out to sea and the weather could look great at beaches along Florida, the Carolinas, even up to New England, but everyone needs to be aware of the risks and dangers at the beach," according to AccuWeather Lead Hurricane Expert Alex DaSilva. "We expect the rip current risk along the Atlantic coast of the U.S. to start later this week along the Southeast and ramp up over the weekend, expanding to the north."

Ernesto fifth named storm in 2024 hurricane season

In a revised forecast issued earlier this month, the federal government called for an "extremely active" Atlantic hurricane season , one that could rank among the busiest on record. The National Oceanic and Atmospheric Administration predicted 17 to 24 named storms with about 8 to 13 becoming hurricane-strength, over the average 14 named storms and seven hurricanes.

In a statement, NOAA head Rick Spinrad said the season started "early and violent" with Hurricane Beryl being the earliest Category 5 hurricane in the Atlantic on record. He added the agency's update signifies that the peak of the hurricane season is near, which typically includes the most impactful storms and hurricanes.

Overall, NOAA says there's a 90% chance of an above-average season, which is among the highest chances ever issued by the agency, lead seasonal hurricane forecaster Matthew Rosencrans told USA TODAY.

Ernesto comes on the heels of deadly Hurricane Debby

Ernesto emerged in the Atlantic as residents and authorities across the eastern U.S. were recovering from former tropical storm Debby.

Debby made landfall last week along Florida's Big Bend region as a Category 1 hurricane before the storm's remnants caused major flooding across much of the Eastern Seaboard, inundating entire neighborhoods as authorities conducted water rescues and evacuations. At least eight deaths have been tied to the storm.

In July, Hurricane Beryl pummeled the Caribbean as a major hurricane before slamming Texas, inflicting massive power blackouts that led to several fatal cases of heatstroke. Beryl has been linked to more than 20 deaths across the U.S. and the Caribbean.

Contributing: Doyle Rice, Dinah Voyles Pulver and Jorge L. Ortiz, USA TODAY; C. A. Bridges, Palm Beach Post

This article originally appeared on USA TODAY: Ernesto slams Puerto Rico with heavy rain and strong winds, causing mass power outages