Hurricane Helene forged a devastating path of floods and wind damage after slamming into Florida’s Big Bend region on Thursday night, submerging much of the state’s Gulf Coast before continuing its destructive march through Georgia and into the mountains of Appalachia. More than 40 people were reported dead in four states as the huge storm spawned flash floods and landslides on its way north.

In the densely populated Tampa Bay region of Florida, neighborhoods were underwater on Friday, the result of a powerful storm surge. In southern Georgia, search teams pulled trapped residents, some with injuries, out of damaged buildings. More than two million people in North Carolina were under flood warnings, and millions, including some as far north as Virginia, were without power.

The destruction stretched at least 800 miles north from where the storm came ashore in a sparsely populated area of Florida called the Big Bend, which sits in the crook of coastline where the Panhandle connects to the Florida peninsula.

Near the town of Newport, Tenn., concerns about a potential dam collapse triggered a flash flood warning for 20,000 people and led officials to order many in the 7,000-person community to evacuate. In mountainous western North Carolina, landslides threatened homes and blocked major roads. Emergency officials issued an evacuation warning for residents living below a large dam, the Lake Lure Dam, saying its failure was imminent.