Millions prepare for potentially catastrophic Florence

Walker Townsend, at right, from the Isle of Palms, S.C., fills a sand bag while Dalton Trout, in center, holds the bag at the Isle of Palms municipal

Walker Townsend, at right, from the Isle of Palms, S.C., fills a sand bag while Dalton Trout, in center, holds the bag at the Isle of Palms municipal

Kevin Orth loads sandbags into cars on Milford Street as he helps residents prepare for Hurricane Florence, Monday, Sept. 10, 2018, in Charleston, S.C

Kevin Orth loads sandbags into cars on Milford Street as he helps residents prepare for Hurricane Florence, Monday, Sept. 10, 2018, in Charleston, S.C

Mike Herring with Frank's Ice Company unloads another pallet of ice as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington,

Mike Herring with Frank's Ice Company unloads another pallet of ice as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington,

People shop at the Harris Teeter, filling up on water and supplies as Hurricane Florence becomes a threat to the coast Monday, Sept. 10, 2018, in Char

People shop at the Harris Teeter, filling up on water and supplies as Hurricane Florence becomes a threat to the coast Monday, Sept. 10, 2018, in Char

Alex Gilewicz buys supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Residents of Wilmington and Southeastern N.C. Florence ra

Alex Gilewicz buys supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Residents of Wilmington and Southeastern N.C. Florence ra

Chris Rayner helps customers load their cars as they buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurricane Florence

Chris Rayner helps customers load their cars as they buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurricane Florence

James Wemyss puts out more supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Florence rapidly strengthened into a potentially

James Wemyss puts out more supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Florence rapidly strengthened into a potentially

People buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Florence rapidly strengthened into a potentially catastrophic hur

People buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Florence rapidly strengthened into a potentially catastrophic hur

Brian Franklin prepares more generators for sale as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurricane Flo

Brian Franklin prepares more generators for sale as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurricane Flo

Jim Craig, David Burke and Chris Rayner load generators as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurric

Jim Craig, David Burke and Chris Rayner load generators as people buy supplies at The Home Depot on Monday, Sept. 10, 2018, in Wilmington, N.C. Hurric

This photo provided by NASA shows Hurricane Florence from the International Space Station on Monday, Sept. 10, 2018, as it threatens the U.S. East Coa

This photo provided by NASA shows Hurricane Florence from the International Space Station on Monday, Sept. 10, 2018, as it threatens the U.S. East Coa

In this Monday, Sept. 10, 2018, photo released by the U.S. Navy, the guided-missile destroyer USS Nitze departs Naval Station Norfolk after the announ

In this Monday, Sept. 10, 2018, photo released by the U.S. Navy, the guided-missile destroyer USS Nitze departs Naval Station Norfolk after the announ

Chris Brace, from Charleston, S.C. lowers hurricane shutters on a client's house in preparation for Hurricane Florence at Sullivan's Island, S.C., Mon

Chris Brace, from Charleston, S.C. lowers hurricane shutters on a client's house in preparation for Hurricane Florence at Sullivan's Island, S.C., Mon

Chris Brace, from Charleston, S.C. lowers hurricane shutters on a client's house in preparation for Hurricane Florence at Sullivan's Island, S.C., Mon

Chris Brace, from Charleston, S.C. lowers hurricane shutters on a client's house in preparation for Hurricane Florence at Sullivan's Island, S.C., Mon

Residents of the Isle of Palms, S.C., fill sand bags at the Isle of Palms municipal lot where the city was giving away free sand in preparation for Hu

Residents of the Isle of Palms, S.C., fill sand bags at the Isle of Palms municipal lot where the city was giving away free sand in preparation for Hu

Walker Townsend, at left, from the Isle of Palms, S.C., fills a sand bag while Dalton Trout, at right, holds the bag at the Isle of Palms municipal lo

Walker Townsend, at left, from the Isle of Palms, S.C., fills a sand bag while Dalton Trout, at right, holds the bag at the Isle of Palms municipal lo

Larry Pierson, from the Isle of Palms, S.C., purchases bottled water from the Harris Teeter grocery store on the Isle of Palms in preparation for Hurr

Larry Pierson, from the Isle of Palms, S.C., purchases bottled water from the Harris Teeter grocery store on the Isle of Palms in preparation for Hurr

RALEIGH, N.C. (AP) — Millions of Americans are preparing for what could become one of the most catastrophic hurricanes to hit the Eastern Seaboard in decades.

Hurricane Florence is carrying winds of up to 140 mph as a Category 4 storm. It is expected to strengthen and possibly become a Category 5 storm Tuesday before closing in on North or South Carolina on Thursday.

Mandatory evacuations have been issued for parts of South Carolina, North Carolina and Virginia, including the entire coast of South Carolina.

Since reliable record-keeping began more than 150 years ago, North Carolina has been hit by only one Category 4 hurricane: Hazel, with 130 mph winds, in 1954.