From CNN's Abbie Boudreau and Scott Zamost

NEW ORLEANS, Louisiana (CNN) - As Hurricane Gustav took direct aim at New Orleans, social workers and homeless advocates spent the last few hours before the evacuation deadline looking for the homeless.

Early Sunday morning, Mike Miller from the group Unity of Greater New Orleans was clambering into abandoned buildings, looking for signs people had been sheltering there.

"Watch out for the nails," he warns as he steps inside.

Miller says that there are more than 71,000 abandoned and blighted buildings in New Orleans and many have become shelters for the city's homeless. He says that since the homeless don't have TV, radio or newspaper subscriptions, word of mouth is the only way to warn of the imminent storm.

"How do you find those people, how many of those people will be missed? Miller asks. "Is that the kind of thing you can only count after a body toll?"

In building after building, Miller shouts inside, but gets no answer.

Under a bridge, he finds one homeless man and warns him that the last bus will soon be leaving the city.

"I'll be there," the homeless man promises.

"Beautiful," Miller responds.

In a nearby park Miller is cheered to see only five people, instead of the 35 who were three two nights before.

Among the five is a man who goes by the name Guitar Mike. He says that he doesn't plan to leave.

"There ain't no water coming," he insists. "It's not going to happen."

"I went through Katrina, and I survived that one," Guitar Mike says. "And if it does happen, I will survive this one."

The exchange is frustrating for Miller, who all night has been offering to drive people to the bus station himself.

A few minutes later, Miller finally finds a taker, a man who has just gotten out of jail after being caught sleeping in an abandoned house.

"Get on that bus," Miller tells him.

WASHINGTON (CNN) - Federal Emergency Management Agency Administrator David Paulison said Sunday that his agency had gathered thousands of meals, liters of water and other supplies for evacuees ahead of Hurricane Gustav's expected arrival.

He said the supplies, which also included cots and generators, could be quickly moved "wherever the storm happens to make landfall."

Like other officials, Paulison urged Gulf Coast residents to evacuate, particularly those in New Orleans. "I cannot emphasize enough the need to evacuate the city," he said, speaking a news conference.

He also encouraged evacuees to register with FEMA's family registry locator system, so family members could locate them. There was no such system in place during Hurricane Katrina in 2005, "and it was very difficult for families to locate family members," he said.

The registration could be accessed via FEMA's Web site - www.fema.gov - or by calling the agency at 1-800-588-9822, he said.

"I told you before we were going to be ready for this storm," he said. "I think we're showing you we are ready for this storm.

"Again, we cannot - I can't stop the damage from happening. We can't stop the storm from coming in. What we can come is be as ready as possible," he said.

Paulison said a number of hospitals that had planned to ride out the storm were now moving critical-needs patients, and several nursing homes had asked for help at the last minute. The majority of those in the nursing homes were bedridden, he said.

"We had to get extra resources in there," he said, particularly aircraft. Texas National Guard, U.S. Northern Command and others are helping, he said. "It looks like now we're going to have enough aircraft to get everybody out."

Richard Rowe, Northcom's chief operations officer, said he expected Northcom to fly some 1,300 patients out of the Gulf Coast region, and said the command had begun to move up to 16,000 other people out of New Orleans. They were flying them to Nashville, Tennessee; San Antonio, Texas; Louisville, Kentucky; and Fort Smith, Arkansas, he said.

Rear Admiral Sally Brice-O'Hara of the U.S. Coast Guard told mariners to get out of harm's way. "Mariners have to heed the advice, take precautions, find safe haven, stay out of this weather," she said at the same news conference.

(CNN) - Republican presidential candidate John McCain said most activities at the GOP convention in Minnesota will be suspended on Monday because of Hurricane Gustav.

"This is a time when we have to do away with our party politics and we have to act as Americans. We have to join the 300 million other Americans on behalf of our fellow citizens. It's a time for action. So, we're going to suspend most of our activities tomorrow except for those absolutely necessary," said McCain, speaking from St. Louis.

McCain's top campaign aide said other party officials say the session will be truncated, and officials will carry out minimum requirements to open the convention.

Speaking at the convention site in St. Paul, Minnesota, Rick Davis said, "There are certain basic minimal requirements of constituting the party and convention that are required." He said the convention will open at the regularly schedule time, at 3 p.m., and end around 5:30 p.m.

"I would say that the main information I can give you today is that owing to the fact that the senator has asked us to take our Republican hats off and put our American hats on, tomorrow's program will be business only, and we'll refrain from any political rhetoric that would be traditional in an opening session of a convention," Davis said.

WASHINGTON (CNN) - The American Red Cross said on Sunday it is starting to receive evacuees in shelters throughout the Gulf Coast as Hurricane Gustav approaches.

The agency - which has relief operations ready in Alabama, Mississippi, Louisiana and Texas - says it is the largest Red Cross relief effort since Hurricane Katrina.

It urges evacuees to bring medical supplies, toiletries, clothing and bedding, games and "comfort items" for chidren, disaster supplies, such as flashlights, car keys and keys for friends' or relatives' homes.

(CNN) - The McCain campaign has arranged a flight from St. Paul, Minnesota to Jackson, Miss., for GOP delegates who want to return to the Gulf Coast region, said Louisiana state party chairman, Roger F. Villere, Jr.

The same plane will carry family members of delegates who want to fly out of harm's way from Jackson to the Minneapolis-St. Paul region, Villere said. The campaign has conferred with all of the state chairpersons in the Gulf Coast region.

"I can't even express to you how helpful they have been," said Villere, referring to the McCain campaign. Some Republican delegates have already left or plan to leave St. Paul, but it is not clear how many.

(CNN) - Coastal Louisiana could experience tropical storm force winds from Hurricane Gustav as early as Sunday night, Louisiana Gov. Bobby Jindal said, as he made a last appeal for residents to evacuate.

"Don't just look at landfall. Look at those tropical storm force winds," he said. "That's when it will not be safe to be driving or be on the road."

Tropical storm winds range from 39 mph to 73 mph, according to the National Hurricane Center.

Hurricane Gustav, with sustained winds of maximum winds of 115 mph with higher gusts, is currently a Category 3 hurricane, the NHC said. Its hurricane force winds extend outward up to 50 miles, while its tropical force winds extend up to 200 miles.

"There is still time for our people to evacuate," Jindal said. "We need to take this storm very seriously. Whether it's a strong Category 3 or border-line Category 4, you're going to see strong tidal surge, strong wind speeds. The National Hurricane Center doesn't know precisely where the storm will strike Louisiana's coast," he said.

"The important thing though is for people to take these warnings, take this opportunity very seriously. Now is the time to get out of harm's way."

Maps of Gustav's path shows that it could strike southern Louisiana and other areas battered by Hurricane Katrina in 2005.

All but three of Louisiana's 64 parishes had declared an emergency, and Jindal said nearly every parish along the coast had issued a mandatory evacuation.

"I strongly encourage people to heed those evacuations and warnings," he said.

Jindal said officials were working to evacuate hospitals and nursing homes. "I strongly, strongly encourage those nursing homes that are non-mandatory evacuation parishes to also evacuate," he said.

Earlier Homeland Security Secretary Michael Chertoff said a number of Louisiana hospitals that had planned to ride out the storm were now moving critical-needs patients.

Because of that change, "we've had to increase tempo of our air flights," he said.

(CNN) - Hurricane Gustav weakened slightly in the early afternoon hours Sunday but still was predicted to be a major hurricane when it smack into the Gulf Coast sometime Monday.

Hurricance Gustav was barreling toward southern Lousiana, sending Hurricane Katrina survivors fleeing and prompting President Bush to alter his plans and forcing New Orleans Mayor Ray Nagin to institute a curfew.

As of 2 p.m. ET, the eye of the Category 3 storm was about 270 miles (435 km) southeast of the mouth of the Mississippi River, the National Hurricane Center in Miami said.

The storm was moving at 17 mph across the central Gulf of Mexico on Sunday and is expected to reach the U.S. Gulf Coast on Monday, forecasters said.

The storm had maximum winds of 115 mph with higher gusts, making it a Category 3 hurricane, forecasters said. The storm could increase to Category 4 storm, with winds of 131 to 155 mph, forecasters said.

Maps of Gustav's path show that it could strike southern Louisiana and other areas battered by Hurricane Katrina in 2005.

That storm hit the area at a Category 3, caused severe flooding and killed more than 1,800 people.

The White House said Sunday that Bush and Vice President Dick Cheney will not attend the Republican National Convention Monday as planned because of Hurricane Gustav, the White House said Sunday.

The president had been scheduled to address delegates in St. Paul, Minnesota, Monday night.

Bush Sunday warned residents of the Gulf Coast that a "serious" storm was headed their way. He said he planned to head to Texas to meet with emergency workers and evacuees.

"This storm is dangerous," Bush warned, urging resident to heed calls by state to evacuate.

Republican officials are monitoring the storm and said it could cause "substantial" changes to the convention program.

Presidential candidate John McCain hinted at the potential changes to reporters gathered in Pearl, Mississippi, Sunday.

"We must redirect our efforts from the really celebratory event of the nomination of president and vice president of our party to acting as all Americans," McCain said. "We'll change our program and I'll be announcing details of it in the next few hours."

Gustav killed at least 51 people in southwestern Haiti and eight in neighboring Dominican Republic last week before moving on to Cuba. It was in the Caribbean Friday and intensified just before it hit Cuba.

Roadways heading out of Lousiana were clogged with cars Sunday, CNN personnel observed.

Louisiana resident Nick Dominque, 30, said he would stay behind to look after his parents who live in southern part of the state.

Dominque was one of the many I-Reporters who contacted CNN. He said he had weathered Hurricanes Rita and Katrina.

"This is a very dangerous storm and we are all hoping for the best," said Dominque. "I have older parents, and living in South Louisiana, they think that they can handle any storm that hits. So I'm going to bunker down and stay with them. I never thought after Rita that I would try to ride out another storm. But here I am again."

Aaron Broussard, president of Louisiana's Jefferson Parish called for a mandatory evacuation of the area Sunday morning. The evacuation will start at noon Sunday, the same time New Orleans officials scheduled the evacuation of that city.

As he reiterated his call urging New Orleanians to leave, Nagin said Sunday the city imposed a "dusk to dawn" curfew and in the afternoon plans to cease its efforts to help people leave the city.

Nagin said the city-wide curfew would continue until the threat of the storm passes, and he warned that looters would be dealt with harshly.

"Anybody who's caught looting in the city of New Orleans will go directly to Angola (Louisiana State Penitentiary    State)," he said.

Local and federal officials - eager to prove they are ready for the storm - urged residents across the region to flee. Many of those residents obeyed, moving north by the tens of thousands, according to Louisiana Gov. Bobby Jindal.

Charter flights, paid for with federal funds, carried thousands of evacuees to other southern cities, including Knoxville, Nashville and Memphis in Tennessee.

Late Saturday night, several hundred New Orleans' citizens stepped off a jet at the Tennessee Air National Guard hangar at Nashville's airport to find an organized registration process and buses ready to take them to temporary shelters, part of a detailed plan developed in response to criticism in the aftermath of Katrina's chaos.

Homeland Security Secretary Michael Chertoff said authorities are responding to Hurricane Gustav better than they reacted to Hurricane Katrina three years ago.

Speaking to reporters outside Andrews Air Force Base in Maryland on Sunday before he headed to the Gulf Coast, Chertoff said he has been pleased with the evacuation process, which started a full day ahead of when evacuations began during Katrina.

In Mississippi, which was also badly damaged by Katrina, Gov. Haley Barbour said his state would cooperate with Louisiana's "contraflow" plan, so that Louisiana evacuees and those in low-lying coastal areas of Mississippi could flee northward.

(CNN) - Hurricane Gustav could cause $29.3 billion in property damage when the storm hits the U.S. Gulf Coast, according to a federally supported computer projection issued on Sunday.

Along with the property damage, business interruption losses are estimated to be $5.1 billion, according to estimates from HAZUS-MH, a software program that crunches numbers calculating potential losses from disasters such as floods, hurricane winds, and earthquakes.

The numbers show that nearly 4.5 million people and 1.6 million buildings in parts of Louisiana and Mississippi will be in the path of the storm.

About 232,500 buildings, around 14 percent of the buildings in the region, will be moderately damaged and 59,953 structures will be destroyed, the projection says. Most of the buildings are classified as residential.

About 28.4 million tons of debris will be generated, and 170 hospitals, 599 fire stations and 568 police stations will be in the path of the storm, the projections said.

"Before the hurricane, the region had 25,594 hospital beds available for use. On the day of the hurricane, the model estimates 14,088 hospital beds (only 55.00 percent) are available for use. After one week, 75.00 percent of the beds will be in services. By 30 days, 84.00 percent will be operational," the report said.

The projection estimates 116,700 households will be displaced because of the hurricane and of those 32,901 people "will seek temporary shelter in public shelters."

The numbers reflect the growing strength of the storm, now at Category 3, and there are expectations that New Orleans will be hit hard by the hurricane.

Developed by the Federal Emergency Management Agency and the National Institute of Building Sciences, the HAZUS-MH estimates are designed to help officials cope with impending disasters.

The projections are updated several times daily.

(CNN) - Louisiana Gov. Bobby Jindal said that coastal Louisiana could experience tropical storm force winds from Hurricane Gustav as early as Sunday night.

"Don't just look at landfall. Look at those tropical storm force winds," he urged residents. "That's when it will not be safe to be driving or be on the road."

Tropical storm winds range from 39 mph to 73 mph, according to the National Hurricane Center
Hurricane Gustav, with sustained winds of 120 mph is currently considered a Category 3 hurricane, the NHC said.

Its hurricane force winds extend outward up to 50 miles, while its tropical force winds extend up to 200 miles.

NEW YORK (CNNMoney.com) - The world oil market's reaction to the gathering threat of Hurricane Gustav will be put to the test in a special trading session on Sunday afternoon.

Electronic trading will begin several hours early at 2:30 p.m. ET, according to the CME Group, which runs the New York Mercantile Exchange and Globex electronic trading system.

This is the first time that NYMEX has extended trading for an emergency.