Millions of Americans have been left without power following Hurricane Helene’s deadly assault on the Eastern U.S.

South Carolina was the worst-affected state, with 1,089,535 outages recorded as of early Saturday, according to PowerOutage.us, a service that tracks disruptions. In South Carolina’s Greenville County alone, 258,688 outages were recorded.

Hurricane Helene made landfall in Florida on Thursday as a powerful category 4 storm. Forecasters warned of “a catastrophic and deadly storm surge.” It was the strongest hurricane on record to landfall in Florida’s Big Bend region, The Weather Channel reported.

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Some 787,428 outages were recorded in Georgia, 728,427 in North Carolina, 527,945 in Florida, 224,841 in Ohio, and 141,407 in Kentucky. There were an additional 72,962 in Indiana, 70,991 in West Virginia, and 62,091 in Tennessee, for a combined total of 3,705,627.

South Carolina Governor Henry McMaster said on X, formerly Twitter, that work was underway to clear roads and restore power, but he added that this would “take some time, many days in some places.”

The National Hurricane Center (NHC) warned power outages could be long-lasting and recommended anyone using generators to place them at least 20 feet away from doors, windows, and garages to avoid deadly carbon-monoxide poisoning.

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“Helene has rapidly intensified today while nearing landfall in the Florida Big Bend,” the NHC said in a forecast discussion earlier on Thursday. “It should be emphasized that Helene is at the upper bound of hurricanes in terms of storm size, and impacts are and will occur well away from the center.”

Helene became a tropical storm on Tuesday, becoming the season’s most powerful hurricane by the time it reached land.

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The Federal Emergency Management Agency (FEMA) urged those in Helene’s path “to take immediate action to protect themselves as the storm approaches,” highlighting a “risk for dangerous flash and flooding in Alabama, Georgia, North Carolina and South Carolina.”

An update from the NHC late Friday warned of “record-breaking” flooding across the southern Appalachians, but said that conditions would begin to improve Friday night and on Saturday “following the catastrophic flooding over the past two days.”

The agency said deadly hazards could remain after the system had passed, including downed power lines and flooded areas.

Tennessee House candidate Brad Batt shared an image to X (formerly Twitter), which appeared to show around three-dozen people taking refuge from high floodwaters on a hospital roof.

A tally by The Associated Press and U.K. newspaper The Guardian showed that Helene—now rated a post-tropical cyclone by the NHC—has killed more than 40 people.

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