Hurricane Earl gained strength late Wednesday to a Category 4 storm with 135 mph winds, after being downgraded to a Category 3 storm earlier in the day.
Parts of coastal North Carolina have already started evacuations and a hurricane watch was issued for much of the East Coast.
The National Hurricane Center said it has been nearly 20 years since a hurricane of this size threatened so much of the Eastern Seaboard. Residents from the Carolinas to New England are taking the advice of officials and are making preparations ahead of Earl.
Click here to track AccuWeather's radar on Hurricane Earl.
Forecasters are predicting the storm could deal a glancing blow to North Carolina as it makes its closest approach to Cape Hatteras on Thursday.
"We're telling people to keep that weather eye, set your options early, and as always be prepared," said Chief George Baker of Barnstable, Mass. Emergency Planning.
"It's going to be too close to the coast not to be ready to go," said Craig Fugate, administrator of the Federal Emergency Management Agency.
Summer tourists are have also taken heed of the approaching storm.
"I've always left, when they said it was coming, I left," said tourist Adrian Powell.
In the Caribbean, Earl left a trail of downed power lines, damaged homes and crowded emergency shelters.
As Earl continues its march toward the U.S. Coast, North Carolina's governor has told coastal residents to be ready to evacuate.
"Any person who lives on the coast of North Carolina, or any person who has reason to think the storm track might go over their house, ought to go out, and gather up those supplies," Gov. Bev Perdue, D-N.C., said. "Could have been that water-tight box, it doesn't cost a lot to buy batteries and snacks and water to get through three-four days."
Virigina Gov. Bob McDonnell (R) plans to declare an emergency in order to muster emergency personnel for the Commonwealth.
Meanwhile, President Barack Obama is also keeping up to date on the storm, participating in a call Wednesday with FEMA about preparations for the government's response to the hurricane, if necessary.