Flash flood emergencies are ongoing in multiple states.
Helene made landfall in Florida's Big Bend region Thursday night as a massive Category 4 hurricane -- the strongest hurricane to make landfall in the Big Bend on record.
Helene has since weakened to a tropical depression and is now pushing through Georgia and the Carolinas, bringing catastrophic rainfall and life-threatening flash flooding as the storm moves toward Tennessee.
In Valdosta, Georgia, search and rescue teams are trying to reach people trapped inside heavily damaged buildings, Georgia Gov. Brian Kemp said.
"We are asking for patience as we prioritize critical medical emergencies and essential services,” he said.
Helene hit especially hard between Valdosta and Augusta.
Atlanta is facing major flooding.
More than 4 million customers lost power across the South Friday in the wake of Hurricane Helene.
Over 1 million customers are without power in Georgia and 900,000 are without power in Florida.
More than 50 health care facilities are operating on generator power across Florida, officials said.
Another 1.2 million are without power in South Carolina and 700,000 are without power in North Carolina.
Mandatory evacuations are in place for some residents of Asheville in western North Carolina as "catastrophic rain" causes severe flooding in the region.
Over 100 people have been rescued from the rising waters and numerous landslides have been reported during the "fierce storm," North Carolina Gov. Roy Cooper said Friday.
Cooper said the "priority now is saving lives."
North Carolina faces flooding emergency
"People in western North Carolina should consider all roads closed unless you are seeking higher ground," he said.
Parts of North Carolina have recorded up to 15 inches of rain, with more expected through Friday. Some areas are expecting as much as 20 inches
-ABC News’ Max Golembo and Matt Foster
A flash flood emergency has been issued in Atlanta, where 4 to 6 inches of rain has fallen so far.
Flooding from Helene prompts water rescues in Georgia
More than 25 people have been rescued from life-threatening floodwaters in Atlanta, officials said.
Unexpected swift currents trapped a family of two adults and an infant on top of their car, and crews used a rope and a boat to help them to safety, Atlanta Fire Rescue said.
Another 1 or 2 inches of rain is possible, and the rainfall rate is expected to be 1 to 2 inches in 1 hour, the National Weather Service said.
Residents are urged to seek higher ground.
Atlanta Public Schools are closed on Friday.
Flash flood emergencies are also in effect in Asheville, North Carolina, and Clemson, South Carolina.
-ABC News' Faith Abubey
