Hurricane Helene live updates: 52 dead across the South from catastrophic storm

Dozens of people were safely evacuated from the roof of Unicoi County Hospital in Erwin, Tennessee, hospital officials said.

Fifty-four patients and staff became trapped on the roof amid flooding, according to Virginia State Police. They were all safely evacuated via helicopter rescues, officials said.

"I don't think very many people have seen something like this before," Ballad Health CEO Alan Levine said during a press briefing following the rescue. "The most important thing is the safety of our employees and patients. Thank God, thanks to the great work of Tennessee and Virginia partnering to help us get this rescue underway, they're all safe."

The patients were being transported another hospital, he said.

President Joe Biden told reporters that the impact of Hurricane Helene "looks bad," citing more than two dozen dead, but that they "don't have enough information."

He was asked by ABC News' Karen Travers about his briefing with his team on the storm effects while on the tarmac in Rehoboth Beach, Delaware, Friday afternoon.

-ABC News' Michelle Stoddart

Helene has been downgraded to a tropical depression but it is still bringing catastrophic and potentially life-threatening flooding to the Southeast. People should be prepared for flash flooding, river flooding and landslides.

Busick, in western North Carolina, recorded nearly 30 inches of rain this week from Helene and a previous storm.

Meanwhile, water levels are receding along Florida’s Gulf Coast after Hurricane Helene’s intense storm surge. Water levels reached more than 15 feet above ground level in some areas.

Helene is expected to continue to weaken and stall over the Tennessee and Ohio valleys this weekend, bringing more heavy rain, gusty winds and flooding.

A flood watch is in effect from Missouri to Virginia. Up to 6 inches of rain is possible in some areas.

A tornado watch is also in effect for parts of North Carolina and Virginia. Several tornadoes have already been reported in North Carolina.

When dangerous floodwaters quickly surrounded Tennessee’s Unicoi County Hospital and seeped inside the building, many inside could no longer be safely evacuated and were forced to relocate to the roof, according to the hospital.

Fifty-four people are trapped on the roof and seven are in rescue boats, according to Ballad Health.

"The flooding of the property happened so quickly the ambulances could not safely approach the hospital," hospital officials said. It was too dangerous for boats to evacuate the hospital, and due to the high winds, helicopters can’t help with evacuations, officials said.

"The situation at the hospital is very dangerous," officials said. State and local rescuers "are engaged in what can only be described as a dangerous rescue operation."

-ABC News’ Alexandra Faul