Hurricane Florence weakened slightly Wednesday to Category 3, but remains a dangerous storm while moving toward the coasts of North and South Carolina.

In its 2100 GMT public advisory, the US National Hurricane Center (NHC) said that Florence has maximum sustained winds of 195 kph (120 mph), extending outward up to 110 km (70 mi) from the center of the storm.

The tropical-storm-force winds extend outward up to 315 km (195 mi).

The NHC warned that the "combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline."

"Although slow weakening is expected to begin by late Thursday, Florence is forecast to be an extremely dangerous major hurricane when it nears the U.S. coast late Thursday and Friday," the Miami-based NHC said.

Florence is located about 615 km (385 mi) southeast of Wilmington, North Carolina, and some 675 km (420 mi) east of Myrtle Beach, South Carolina, while moving northwest at 26 kph (16 mph).

The NHC issued a hurricane warning for South Santee River, South Carolina, to Duck, Albemarle and Pamlico Sounds, North Carolina, as well as a hurricane watch for Edisto Beach, South Carolina, to the North Carolina-Virginia border.

A storm surge warning has also been sent out for the area, and the NHC warned that there is "danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours."