Lines of people waiting for buses to take them out of the city grew longer Saturday and traffic grew heavier on main highways as Hurricane Gustav strengthened into a dangerous storm on track for the Gulf Coast.

A line well over a mile long stretched in six loops through the parking lot at Union Station Terminal. Under a blazing sun, many led children or pushed strollers with one hand and pulled luggage with the other. Volunteers handed out bottled water, and medics were nearby in case people became heatsick.

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Joseph Jones Jr., 61, wore a towel over his head to block the sun. He'd been in line 2 1/2 hours, but wasn't complaining. During Katrina, he had been stranded on a highway overpass.

"I don't like it. Going someplace you don't know, people you don't know," Jones said. "And then when you come back, is your house going to be OK?"

The city had yet to call for a mandatory evacuation, but began ushering out the sick, elderly and those without their own transportation on Saturday. The state has a $7 million contract for more than 700 buses to carry an estimated 30,000 people to shelters.

Many residents said the evacuation was more orderly than Hurricane Katrina, which struck three years ago Friday. But not everyone was happy.

Elizabeth Tell, 67, had been waiting on the corner since 6:30 a.m. for a special needs bus to take her and her dog, Lee Roy, to the station. It was three hours before the first bus arrived, completely full of people in wheelchairs.

"They're not taking care of us down here!" she shouted as the brown-and-white spotted hound mix panted inside his hip-high plastic kennel.

Many residents weren't waiting for a formal evacuation call. Cars packed with clothes, boxes and pet carriers drove north among heavy traffic on Interstate 55, a major route out of the city. Gas stations around the city hummed. And nursing homes and hospitals began sending patients farther inland.

"I'm getting out of here. I can't take another hurricane," said Ramona Summers, 59, whose house flooded during Katrina. She hurried to help friends gather their belongings. Her car was already packed for Gonzales, nearly 60 miles away to the west of New Orleans.

Police and firefighters were set to go street-to-street with bullhorns over the weekend to help direct people where to go. Unlike Hurricane Katrina, there will be no shelter of last resort in the Superdome. The doors there will be locked.

Those among New Orleans' estimated 310,000 to 340,000 residents who ignore orders to leave accept "all responsibility for themselves and their loved ones," the city's emergency preparedness director, Jerry Sneed, has warned.

There were signs Saturday morning of people racheting up their plans to leave. ATM machines were running out of cash. Long lines were sprouting up at gas stations as motorists filled up their cars. Cases of bottled water were selling briskly at convenience stores.

Gustav swelled into a major hurricane south of Cuba and could strike the U.S. coast anywhere from Mississippi to Texas by Tuesday.

Forecasters said if Gustav follows the projected path it would likely make landfall on Louisiana's central coast, sparing New Orleans a direct hit. But forecasters caution it is still too soon to say exactly where the storm will hit.

"Any little jog could change where it makes landfall," said Karina Castillo, a hurricane support meteorologist at the National Hurricane Center said.

One shop along Magazine Street, its windows covered up, showed a flash of New Orleans' storm humor. "Geaux Away Gustav," it read, giving it a French flair.

President Bush called Gulf Coast governors Saturday and told them they would have the full support of the federal government, White House spokesman Scott Stanzel said.

Officials plan to announce a curfew that will mean the arrest of anyone still on the streets after a mandatory evacuation order goes out. Police and National Guardsman will patrol after the storm's arrival, and Gov. Bobby Jindal has said he requested additional search and rescue teams from other states.

Jindal also said the state would likely switch interstate lanes on Sunday so that all traffic would flow north, in the direction an evacuation would follow.

At 11 a.m. EDT, the center of Gustav was about 185 miles east of the western tip of Cuba. The storm had maximum sustained winds of 125 mph, just 6 mph shy of the Category 4 threshold. The center of Gustav was to pass over western Cuba later Saturday and strengthening is forecast after it reaches the Gulf of Mexico.

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