North Carolina Gov. Roy Cooper described Helene as an unusually dangerous storm that threatens to bring heavy rain and potentially catastrophic flooding to central and western North Carolina on Thursday night and Friday.

Helene is forecast to drop more than 1 foot of rain to parts of western North Carolina, and even cities like Charlotte could see flash flooding despite not being in the storm's direct path, officials said.

President Joe Biden has approved emergency declarations for states in Helene's path, including North Carolina.

-ABC News’ Alex Faul

Helene is forecast to strengthen to a major Category 3 hurricane with 120 mph winds by 8 p.m. Thursday.

Landfall is expected Thursday night, between 10 p.m. and midnight, southeast of Tallahassee.

After landfall, the fast-moving Helene will push strong winds inland to northern Georgia.

On Friday morning, catastrophic flash flooding is a major threat from northern Georgia to Asheville, North Carolina. That area already saw up to 6 inches of rain over the last 24 hours from a separate storm, and Helene could drop another 10 to 20 inches of rain.

The remnants of Helene will stall over the weekend in the Tennessee, Ohio and Mississippi River valleys. Flooding is possible in Tennessee, Kentucky and Arkansas.

-ABC News’ Max Golembo

Helene is now a Category 2 hurricane with 105 mph winds as it barrels toward the Florida Panhandle.

Category 3 -- which is considered a major hurricane -- begins when the storm’s winds reach 111 mph.

Helene is forecast make landfall Thursday night, between 10 p.m. and midnight, as a Category 3 hurricane with 120 winds.

Helene is "very large," so the storm's rain, wind and storm surge "will extend far away from the center and well outside the forecast cone, particularly on the east side," the National Hurricane Center warned.

"Comparing the system with previous hurricanes in the Gulf of Mexico over the past couple of decades, Helene is at the upper bound in terms of size," the NHC said.

-ABC News’ Max Golembo

North Florida residents who are in evacuation zones should leave now, Florida Gov. Ron DeSantis warned Thursday morning, since Hurricane Helene’s outer bands are quickly approaching the coast.

Florida’s Division of Emergency Management has partnered with Uber to provide free rides to shelters for Floridians under a state of emergency. Riders can use the code HeleneRelief, officials said.

At least 80 health care facilities -- including hospitals and nursing homes -- are evacuating, officials said.

One of the biggest hazards is falling trees, DeSantis said. He urged people to take cover if they hear trees cracking.

-ABC News’ Alex Faul