All along the US East Coast, people made contingency plans, as the US Navy ordered dozens of vessels out to sea to ride out the storm.

Long lines of cars, pickup trucks and SUVs flowed inland in waves Tuesday as authorities ordered the evacuations along the North Carolina coast.

"We're leaving. Everybody's leaving," said Nick Napolitano, the owner of the Ocean Side Court vacation cottages, whose occupants sometimes ride these things out.

"This one had 160 miles-per-hour winds and they were talking about 40-foot waves. We get something like that and the Outer Banks are going to end up in Raleigh."

An Isabel downgraded to Category Two on the Saffir-Simpson scale from a top level Category Five at the weekend, was still nonetheless packing maximum sustained winds close to 177 kilometers (110 miles) an hour with higher gusts.

Little change in Isabel's strength is forecast prior to landfall, the Miami-based National Hurricane Center said at 0900 GMT Wednesday.

"Hurricane force winds extend outward up to 145 miles (233 kilometers) from the center ... and tropical storm force winds extend outward up to 260 miles (418 kilometers)," it added in a statement.

Isabel is expected to make landfall early Thursday, according to the Center.

Forecasters said it would pack its first punch in North Carolina and then sweep up the seaboard towards Washington. Nearly 50 million people live in the path Isabel is expected to take.

North Carolina and Virginia both declared a state of emergency.

North Carolina Governor Mike Easley urged people to "stock up on needed supplies such as gasoline and water, and tune to news broadcasts to hear the latest updates from emergency management personnel."

Easley Tuesday declared a state of emergency to accelerate relief, as officials warned more than 150,000 people to retreat inland.

As many as 300 North Carolina National Guardsmen will be activated by Wednesday, strengthening the more than 1,800 Guard troops already on active duty and 4,800 to be called up. North Carolina has 5,000 additional troops available, officials said.

"We're completely focused on how do we protect the people of this state - how do we prepare our property," Easley said. "Then we'll worry about how we're paying for it. We're sparing no expense."

Thousands of home and store owners from South Carolina to Virginia and Maryland rushed to board up windows and buy emergency food, batteries and first aid kits. Several hardware stores reported shortages.

Todd Liston, 34, screwed sheets of plywood onto the metal frame of the windows of the offices of his seaside pool company in Kitty Hawk.

This hurricane "looks pretty serious, more than usual," said Liston. "We're pretty prepared here, more than further inland."

Liston said that he has had to board up the windows several times because of hurricanes, including in 1999 for Hurricane Floyd. "Most people kept their plywood from last time," he said.

US warships began steaming out of the giant US naval base at Norfolk, Virginia, to get out of Isabel's path.

Up to 40 submarines and warships, including the carrier USS Ronald Reagan, headed to sea to ride out the hurricane, the US navy said.

Air Force One, President George W. Bush's airplane based at Andrews Air Force Base near Washington, was also ordered to fly inland, officials said.

The air force was to empty six East Coast bases, sending squadrons of fighters, refueling aircraft, transport planes and helicopters to bases to the US Midwest, said a spokeswoman.

A hurricane warning was in effect from Cape Fear, North Carolina, northward to the North Carolina/Virginia state line, meaning that hurricane conditions could be possible within 24 hours, the National Hurricane Center said.

A hurricane watch was in effect from the North Carolina/Virginia state line northward to Chincoteague, Virginia, including Chesapeake Bay and the tidal Potomac River, meaning a hurricane could hit in about 36 hours.

At 0900 GMT Wednesday, Isabel's center was located about 724 kilometers (450 miles) south-southeast of North Carolina's Cape Hatteras.

The hurricane was heading in a north-northwestly direction at about 14 kilometers (nine miles) per hour. It is expected to pick up forward speed in the next 24 hours, the center said.

"The public must continue to take this storm seriously," said Tim Schott, a spokesman for the National Weather Service.

TERRA.WIRE