Officials around Maryland were making storm preparations Wednesday after the National Hurricane Center posted a hurricane watch and tropical storm warnings for the Maryland and Delaware coasts.
The hurricane watch means that hurricane conditions — including winds in excess of 73 mph — are possible in the watch zone within 48 hours. The tropical storm warning means winds over 39 mph, are expected.
Maryland Gov. Martin O'Malley declared a state of emergency, activating the National Guard to assist with storm work if needed, and authorizing the distribution of stockpiled emergency supplies and equipment.
A strengthened Hurricane Earl was still 565 miles south-southeast of Cape Hatteras as of 8 p.m. Wednesday. Top sustained winds had increased to 140 mph, making Earl a Category 4 storm again.
Forecasters said Earl was on track to near the North Carolina shore late Thursday or early Friday and then blow north along the coast, with forecasters cautioning that it was still too early to tell how close the storm might come to land.
Hurricane warnings were posted Wednesday for the North Carolina coast, including the Outer Banks, Pamlico and Albemarle sounds, meaning that hurricane conditions are expected. Visitors were asked to evacuate the vulnerable barrier islands.
Hurricane watches were up from the North Carolina-Virginia border to Cape Henlopen, Del., the mouth of the Chesapeake Bay, and for parts of southeastern Massachusetts, including the islands of Martha's Vineyard and Nantucket.
In Maryland, officials were preparing for any storm scenario.
Ocean City officials said on the town's website that they were expecting sustained winds of 30 to 40 mph with gusts of 50 to 55 mph, 1 to 2 inches of rain and minor to moderate flooding in low-lying areas during high tides Friday into Saturday.
They asked residents, visitors and contractors to secure loose objects such as trash cans, lawn furniture and construction materials.
Ocean City spokeswoman Donna Abbott said visitors were encouraged to monitor conditions and delay travel to the resort until after the storm has passed Friday.
After performing many rescues due to storm-related rip currents Wednesday morning, the Ocean City Beach Patrol limited bathers to knee-deep water for the rest of the day.
Swimming restrictions for the weekend will depend on conditions, Abbott said, but a full complement of guards will be on duty and the beaches will not be closed.
Earl will "be past here very quickly, and we anticipate the remainder of the Labor Day weekend will be excellent weather-wise," she said.
O'Malley said Wednesday during a Board of Public Works meeting that Earl is tracking about 150 miles to 200 miles off Maryland's coast. He said officials expect beach damage and erosion, but that it's unlikely that Ocean City will need to be evacuated.
At the Coast Guard Yard in Curtis Bay, it was all hands on deck as authorities prepared for Earl and a busy holiday weekend.
"We recommend that during this event you stay off the water; there's too much to risk," said Lt. Cmdr. Randy Brown, chief of the Coast Guard's response department for Sector Baltimore.
He urged boaters to pay attention to forecasts, watches and warnings, and to secure their boats and possessions. If they have to go on the water, boaters should file a "float plan" informing family or friends of times and destinations, wear life jackets and carry working radios.
The Coast Guard was securing its vessels, moving at least seven from Yorktown, Va., to safe harbor at Curtis Bay to "make sure that after the storm, we have the capability to respond" to emergencies. Authorities were checking commercial vessels to make sure they are securely moored or ready to move to safety if conditions deteriorate and Baltimore harbor must be closed.
Brown said a cold front approaching from the northwest could pose dangers on the water even if Earl stays away. "We don't want to lose sight of that. … There's some bad weather coming from the west side as well," he said.
Maryland Natural Resources Police will be on full alert, said Sgt. Art Windemuth. "We have mobilized our entire force," the spokesman said. They will be working with federal, state and local authorities as the storm approaches.
While state parks are expected to remain open this weekend, he asked that visitors check the Department of Natural Resources website (dnr.state.md.us) or call the park before heading there.
Jim Lee, meteorologist in charge at the National Weather Service forecast office in Sterling, Va., said Earl, because it is expected to pass well east of the bay, does not pose a threat of serious coastal flooding on the Chesapeake, like that experienced during Isabel in 2003.
He compared this storm to Gloria in 1985 and Bob in 1991, both of which cruised up the Atlantic coast.
But he said people around the Chesapeake Bay should prepare for a 1- to 3-foot storm surge at high tides Thursday afternoon and early Friday. They also should expect an extremely low "blowout" tide Friday evening as winds reverse and drive water out of the Chesapeake.
Earl is expected to bring rough surf and dangerous rip currents to the beaches, and Lee said it will take several days for surf conditions to calm, especially with Tropical Storm Fiona still a factor farther east in the Atlantic.
Mayor Stephanie Rawlings-Blake and other officials urged Baltimore residents to gather water, flashlights and batteries in case high winds and rain from Hurricane Earl and Tropical Storm Fiona flood roads and knock down power lines.
"It seems like God does not want to leave us out for any major weather on the East Coast," said the mayor at a morning news conference in the city emergency operations center.
"The message is to pay attention, to stay informed and to start to prepare," she said. "Any small shift — and this is always the problem in Baltimore — could have a major impact."
She recommended that residents have an emergency kit stocked with a flashlight and extra batteries, a battery-operated radio and a three-day supply of water so they can shelter in place.
Families should develop a plan and check on their neighbors or relatives who might have special needs. People should call 311 if they need assistance, but if residents are prepared with basic necessities, emergency personnel can focus on responding to major problems, Rawlings-Blake said.
The city is prepared to help residents or to provide aid to surrounding communities, said Robert Maloney, director of the Mayor's Office of Emergency Management.
Maloney said people who plan to travel the Eastern seaboard during the Labor Day holiday weekend "must be engaged and monitor these storms."
Hurricane season continues through Nov. 30, so residents should use this storm as an opportunity to prepare, he said.
More information is available at http://www.baltimorecity.gov or residents can call 311, he said.
Even as Earl was bearing down on the East Coast and Tropical Storm Fiona was spinning near the northern Leeward Islands, the National Hurricane Center announced late Wednesday the seventh named storm of the season, Tropical Storm Gaston. Far from any land, Gaston posed no immediate threat.
The Associated Press contributed to this article.