Hurricane Erin, which had exploded into a Category 5 powerhouse, was downgraded to a Category 3 storm on Sunday, but rip currents and surf remained "life-threatening" to beachgoers along the U.S. East Coast, the National Hurricane Center said.

The storm, still driving dangerous, 125 mph winds, was centered about 235 miles north-northwest of San Juan, Puerto Rico, at 2 p.m. ET, the NHC said. Just a day earlier, Erin's sustained winds had reached 160 mph.

Erin, still a major hurricane, is the fifth named storm of the Atlantic hurricane season and the first to reach hurricane status. And Erin is growing in size, a trend expected to continue over the next few days, the hurricane center said.

The storm's dangerous eyewall will most likely remain at sea, but the storm can do damage from afar, AccuWeather warned. The government of the Bahamas on Aug. 17 issued a tropical storm warning for the southeast Bahamas.

"Combined with any shifts in track, this could bring tropical storm-to-hurricane conditions to parts of the U.S. Atlantic Coast," AccuWeather warned.

Richard Pasch, senior Hurricane Specialist for the hurricane center, was among forecasters warning that Erin was expected to produce life-threatening surf and rip currents along the beaches of the United States, Bermuda, and Atlantic Canada for several days.

Puerto Rico avoids 'major impacts' from Erin

Puerto Rico Gov. Jenniffer González said public schools and government offices plan to be open Aug. 18. The University of Puerto Rico's Río Piedras campus will be open if power can be restored promptly, she said.

More than 150,000 LUMA Energy customers were without power midday on Aug. 17. The company posted photos on social media of its employees in the communities working to restore power.

Additional rainfall of 2 to 4 inches, with locally higher amounts to 6 inches, is expected across Puerto Rico through Monday, the NHC said. González urged residents to stay out of the water but said the worst of the storm had moved on.

"Today we should be overcoming the effects of the winds and rain brought by Hurricane Erin, which thank God did not have major impacts in Puerto Rico," González said at a briefing.

Erin aided by warm waters

AccuWeather explains that Erin struggled through relatively cool water and dry air early last week. But it gained momentum quickly from Thursday to Saturday, rolling over much warmer water while surrounded by moisture.

Erin was a tropical storm before gaining hurricane status on Aug. 15. It became a major hurricane early on Aug. 16 when sustained winds exceeded 110 mph to gain Category 3 status, and later that day grew to a Category 5 storm with maximum sustained winds of 160 mph before those winds began to ebb.

Erin's power expected to fluctuate but remain dangerous

Erin has experienced a hurricane phenomenon called an eyewall replacement, AccuWeather Meteorologist Brandon Buckingham said. As the old eyewall expands outward, a new eyewall forms closer to the center.

"Top winds often ease back during this cycle, but it is followed by another surge in wind intensity as the new eye completes organization," Buckingham warned.

Erin's core not expected to reach US shores

Nearly the entire island of St. Thomas in the U.S. Virgin Islands was without electricity early on Aug. 17 — 19,126 out of 23,252 customers, according to PowerOutage.us. Only scattered outages were reported on St. John and St. Croix. The core of Erin is expected to pass to the east of the Turks and Caicos Islands and the southeastern Bahamas late on Aug. 17 and on Aug. 18.

The meteorological services of France and the Netherlands discontinued tropical storm watches for St. Martin, St. Barthelemy, and Sint Maarten, the National Hurricane Center said.

U.S. shores are unlikely to see a direct hit, but a strong offshore hurricane can produce massive and dangerous waves well away from its center, AccuWeather Lead Hurricane Expert Alex DaSilva said.

"The storm is forecast to remain hundreds of miles off the East Coast," DaSilva said, adding that "beaches along the entire East Coast, from Florida to New England and Atlantic Canada, will likely experience rough surf and dangerous rip currents as Erin tracks north and eventually northeast."

'Major coastal flooding' possible in North Carolina

Hurricane Center director Michael Brennan said 50-foot waves could occur near the center and to the right of Erin as the storm moves north, resulting in large breaking waves at beaches along the coast. Wave heights, long-period swells, and life-threatening rip currents — powerful currents of water that can rapidly carry swimmers out to deeper waters — are expected to increase along East Coast beaches by Aug. 18, according to the hurricane center and local National Weather Service offices.

Even from far offshore, "the threat for life-threatening rip currents, damaging beach erosion, major coastal flooding and extremely dangerous surf is increasing," the National Weather Service office in Morehead City, North Carolina, said on Aug. 17. Wave heights could range from 12 to 20 feet along the Outer Banks, the office reports.

AccuWeather said Portions of the Outer Banks and the Virginia beaches will experience a storm surge up to several feet and "significant" coastal flooding and beach erosion. North Carolina's Highway 12 could see heavy overwash with closures possible beginning around midweek.

How fast did Hurricane Erin intensify?

Erin quickly exceeded expectations, undergoing a period of strengthening that the hurricane center refers to as "rapid intensification." Erin's burst of intensification will be among the most rapid ever recorded in the Atlantic Ocean.

Erin's winds increased 45 mph in just 12 hours overnight on Aug. 15, from 75 mph to 120 mph. Ultimately, its wind speeds increased a total of 80 mph in just 18 hours from Friday to Saturday.

In a post-season summary of the 2024 hurricane season, the National Oceanic and Atmospheric Administration reported that Hurricane Milton's rate of intensification — 90 mph in 24 hours in October 2024 — was "among the highest ever observed."

At least two other hurricanes have exceeded that increase. In 2005, Hurricane Wilma's winds increased to 125 mph in 24 hours. In 2007, wind speeds in Hurricane Felix increased by 100 mph in 24 hours, according to hurricane center data.

Hurricane Erin brings heavy rain to Puerto Rico

The tropical storm watch in the Southeast Bahamas means tropical storm conditions are possible within the area for over 24 hours. A tropical storm warning is in effect for the Turks and Caicos Islands, meaning tropical storm conditions are expected within 24 hours.

Rain bands in Erin's expanding quadrants raked Puerto Rico and the Virgin Islands late Aug. 16, with heavy rain and tropical storm force wind gusts of 40 to 50 mph, prompting flash flood warnings in some locations. The National Weather Service warned that up to 8 inches of rain was possible.

On the night of Aug. 16, a buoy near the storm in a north-northeastward direction from San Juan, Puerto Rico, was recording significant wave heights of 22 to 28 feet. That's the average of the highest one-third of waves being measured at the buoy.

What else is happening in the Atlantic?

Storm activity is increasing in the Atlantic Ocean as the 2025 hurricane season reaches the time of year when peak activity traditionally begins. Along with Hurricane Erin, the National Hurricane Center is monitoring two other potential tropical disturbances; one is a couple of hundred miles off the North Carolina coast, with a very low percentage of developing into a tropical storm; another is in the eastern region of the central tropical Atlantic.

A westward-moving tropical wave could produce an area of low pressure in the tropical Atlantic late in the week of Aug. 18, the hurricane center said. But the center shows a 20% chance of storm formation over the next week. If the wave beats the odds and becomes the next named tropical storm, it would receive the name Fernand.

A long-term outlook from the Climate Prediction Center of the National Oceanic and Atmospheric Administration also shows the potential for storm formation increasing between the eastern Caribbean and the African coast. It lists the chances of storm formation in the central tropical Atlantic at greater than 40% during the seven days beginning on Aug. 20.

When did the 2025 hurricane season begin?

The Atlantic hurricane season officially began on June 1 and lasts through the end of November. The Atlantic basin includes the Atlantic Ocean, the Caribbean Sea, and the Gulf of America. Based on a 30-year climate period from 1991 to 2020, the average Atlantic hurricane season has 14 named storms, 7 hurricanes, and 3 major hurricanes, the National Hurricane Center said.

Active hurricane weather typically peaks between mid-August and mid-October.

The eastern Pacific has a slightly longer hurricane season, running from May 15 to November 30. The eastern Pacific basin extends from Mexico and Central America westward.

Contributing: Reuters

This article originally appeared on USA TODAY: Hurricane Erin downgraded to Category 3 but still powerful, dangerous: Live updates

Reporting by John Bacon and Dinah Voyles Pulver, USA TODAY / USA TODAY

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