HOUSTON (AP) -- A slowly weakening Hurricane Rita steamed toward the Texas and Louisiana coast with 125 mph winds Friday, menacing the nation's oil-refining industry. As many as 24 people were killed when a bus carrying nursing-home evacuees caught fire in a traffic jam.
''We're going to get through this,'' Texas Gov. Rick Perry said. ''Be calm, be strong, say a prayer for Texas.''
In New Orleans, Rita's rains breached two patched levees, sending water spilling into already-devastated neighborhoods just days after they had been pumped dry. In the hard-hit but largely empty Ninth Ward, the water gushed through gaps at least 100 feet wide and was soon waist-deep in the streets. Water 6 to 8 inches deep was also rushing into homes in the Gentilly neighborhood, south of the University of New Orleans.
However, officials with the Army Corps of Engineers there was no immediate indication the rest of New Orleans was in danger from the flooding.
Rita weakened during the day to a Category 3 hurricane, down from a fearsome Category 5 with 175 mph winds on Wednesday. It was expected to come ashore early Saturday along the upper Texas-Louisiana coast on a course that could spare Houston and nearby Galveston a direct hit. But it could plow instead into the oil and chemical centers of Beaumont and Port Arthur, about 75 miles east of Houston.
Texas' emergency management coordinator, Jack Colley, predicted Rita would destroy nearly 5,700 homes in the state and cause $8.2 billion in damage.
President Bush planned to visit his home state but canceled at the last moment. The White House said he did not want to slow down the storm preparations.
More than 3 million people along the Texas and Louisiana coasts were urged to get out of the way of Rita, setting off an unprecedented exodus that brought traffic to a standstill across the Houston metropolitan area. Cars overheated and ran out of gas in 10- and 12-hour traffic jams. Some drivers gave up and turned around and went home.
''It can't get much worse, 100 yards an hour,'' fumed Willie Bayer, 70. ''It's frustrating bumper-to-bumper.''
By Friday morning, the freeways within Houston had cleared out, but traffic was still bumper-to-bumper from the outskirts of the city toward Austin and Dallas. The state escorted tanker trucks full of gas to empty stations in small towns along the way. And National Guard trucks delivered gasoline to drivers who ran out.
The bus fire took place in a traffic jam on Interstate 45 near Wilmer, southeast of Dallas. The vehicle was rocked by explosions and engulfed in flames that reduced it to a blackened, burned-out shell.
Early indications were that the bus it caught fire because of mechanical problems, then passengers' oxygen tanks started exploding, Dallas County Sheriff's Department spokesman Don Peritz said.
Dozens of chemical plants are situated along the Texas and Louisiana Gulf Coast in the nation's biggest concentration of oil refineries, and damage and disruptions caused by Rita could cause already-rising oil and gasoline prices to go even higher. Also, environmentalists warned of the possibility of a toxic spill.
Plants shut down operations, and hundreds of workers were evacuated from offshore oil rigs. Texas Gov. Rick Perry said state officials had been in contact with plants about ''taking appropriate procedures to safeguard their facilities.''
At 5 p.m. EDT, Rita was centered about 155 miles east-southeast of Galveston, moving northwest at near 12 mph, and forecasters said it could weaken further become coming ashore.
Its hurricane-force winds extended up to 85 miles from the center, and its tropical storm-force winds reached outward 205 miles, meaning Houston and Galveston might not feel Rita's full fury but could still get battered.
The first bands of rain were expected before nightfall Friday. Forecasters warned of the possibility of a storm surge of 15 to 20 feet, battering waves and rain of up to 20 inches, with more than 25 inches possible over the next several days as the storm moves inland into Texas and Louisiana and wrings itself out.
Two communities that stood to bear the brunt of the storm were Port Arthur, a city of about 58,000 that is home to industries that include oil, shrimping and crawfishing; and Beaumont, a petrochemical, shipbuilding and port city of about 114,000. Beaumont was the site of the 1901 Spindletop oil gusher that gave birth to the modern petroleum industry.
The military sent cargo planes to evacuate medical patients and others from Beaumont. Downtown Beaumont was all but deserted, with buildings boarded up and practically nothing moving but windblown plastic bags. On the horizon, covered in gray clouds, refinery torches belched black smoke.
Sherry Gates, whose husband is maintenance director of the Beaumont Hotel, planned to stay behind to protect the place from looters. The hotel, she said, can withstand whatever Rita brings. ''This old girl,'' she said, ''will see us out.''
In Port Arthur _ a poor, down-on-its-luck town with a largely population of minorities, including Vietnamese shrimp fishermen, and a downtown museum devoted to one of its most famous natives, Janis Joplin _ street lights were turned off. Stores were boarded up along with the homes, many of which sit up on cinderblocks.
Similarly, the usually bustling tourist island of Galveston _ rebuilt after as many as 12,000 people died in a 1900 hurricane that is still the deadliest natural disaster in U.S. history _ was all but abandoned, with at least 90 percent of its 58,000 residents cleared out.
In southwestern Louisiana, up to 500,000 residents along the state's southwest coast were urged to evacuate and state officials planned to send in buses to take refugees.
Rita brought steady rain to New Orleans for the first time since Katrina. The forecast was for 3 to 5 inches in the coming days _ dangerously close to the amount engineers said could send floodwaters pouring back into recently dry neighborhoods.
Dozens of blocks in the impoverished Ninth Ward were swamped after water poured through the sandbags, soil and gravel used to patch the Industrial Canal levee.
''Our worst fears came true,'' said Maj. Barry Guidry of the National Guard. ''We have three significant breaches in the levee and the water is rising rapidly.''
Sally Forman, an aide to Mayor Ray Nagin, said officials knew the levees were compromised but believed the Ninth Ward had been cleared of residents. ''I wouldn't imagine there's one person down there,'' Forman said.
Katrina's death toll in Louisiana rose to 841 Friday, pushing the body count to at least 1,079 across the Gulf Coast. But the company under contract to collect the bodies in the New Orleans area suspended operations until at least Sunday because of the approaching storm.
''Katrina. It's scared everyone,'' said Dianna Soileau, 29, who was fleeing the refinery town of Texas City with her husband and two children. ''We don't want to be the same thing.''
Associated Press writers Pam Easton in Galveston and Liz Austin in Austin contributed to this report.