BEAUMONT, Texas — Hurricane Rita plowed into the Gulf Coast early today, lashing Texas and Louisiana with driving rain, igniting the pre-dawn sky with exploding transformers and threatening to flood the low-lying region.

Rita made landfall at 12:38 a.m. PDT as a Category 3 storm just east of Sabine Pass, on the Texas-Louisiana line, bringing with it a 20-foot storm surge and up to 25 inches of rain, the National Hurricane Center said.

Its 12-mph speed spread worries it would dump 2 feet of rain on flood-prone parts of Texas and Louisiana, spurring tornadoes as it churned north-northwest with winds topping 120 mph.

Texas officials breathed a sigh of relief that Rita spared two flood-prone cities a direct hit. "It looks like the Houston and Galveston area has really lucked out," said Max Mayfield, director of the center.

Rita brought misery even before it hit land, inundating New Orleans with fresh floodwaters as levees weakened by Hurricane Katrina failed to hold off another assault. Outside Dallas, two dozen elderly evacuees from the Houston area were killed yesterday morning when their bus burst into flames fueled by oxygen tanks. In downtown Galveston, Texas, a wind-fueled fire engulfed three buildings late last night.

Nearly 3 million people are estimated to have fled the coastline in a two-day evacuation that caused monstrous traffic jams, worsened by hundreds of vehicles that ran out of gas. Although traffic had lightened noticeably by yesterday afternoon, it was still bumper-to-bumper outside Houston.

In Beaumont, Port Arthur and other refinery towns in the expected path of the storm, nearly all streets and homes were empty as authorities prepared for a storm surge as high as 20 feet. Only a 14-foot levee protects Port Arthur, a town of about 56,000 boxed in by water on two sides.

Although a mandatory evacuation order had been issued for the area, authorities were not trying to force people from their homes. Some residents, despite the increasing urgency of radio and television reports, refused to believe they were in danger.

"You can't run from the good Lord," Eugene Henry, 62, said as he sipped beers with two friends on his stoop in Port Arthur.

But authorities estimated almost all of the other 250,000 people in the Beaumont-Port Arthur area had left. Hospitals and nursing homes were mostly emptied. Inmates were taken from the sprawling, fenced-in prison complex south of Beaumont and put in a crowded — but higher — county jail.

"We don't have the resources to force people out of their homes," Beaumont police spokesman Crystal Holmes said. "But we have made it very clear to them that when we have to take shelter, all emergency services will stop. If people are trapped, or if there is a fire in the city, no help will be coming. The consequences of staying could be death."

Police and rescue personnel settled for the night in fire stations and hospitals. Beaumont loaded hundreds of ambulances, firetrucks, dump trucks and police cars onto two troop transport ships to be ready to offload quickly after the storm.

Shrimp boats and tugboats caught by the shift of the storm's path retreated from the Gulf of Mexico to Sabine Lake and up a narrow shipping channel toward Beaumont, seeking refuge.

In Port Arthur, all stores were closed, buildings boarded. A few law-enforcement officers planned to ride out the storm in a local hotel.

"I've been through them before," said Brian Williams, 33, an officer with the Texas Alcoholic Beverage Commission, one of many agencies pressed into service. "This is just another storm." He paused, then added, "Well, this might be bigger than that."

Hurricanes are guided by steering currents — winds at upper levels of the atmosphere. There often is a brisk steering current blowing west-to-east that moves a storm quickly. In this storm, however, "the steering currents are very, very weak," said National Weather Service meteorologist Jason Hansford in Shreveport, La. "It's going to pretty much stall out."

Deluge predicted

Forecasters don't know how long Rita might sit on the Texas-Louisiana border, but they have a rainfall prediction.

"On the current track ... we're looking at widespread rainfall amounts of 8 to 15 inches with some locations getting 20 to 25 inches," Hansford said.

That's likely to mean severe flash flooding, particularly in low-lying spots and urban areas with heavy concentrations of concrete. In Texas, forecasters warn of such flooding in Texarkana, Nacogdoches, Lufkin, Tyler, Houston and Beaumont; in Louisiana, Shreveport, Bossier City, Lake Charles and possibly Monroe and Alexandria are at risk.

The good news: The area has been dry in recent weeks, meaning lakes, rivers and streams are low and would need heavy, prolonged rain to flood.

However, Steve McCraw, the Texas homeland-security director, said some low-lying communities, such as Beaumont and Port Arthur, could be under water for as many as seven days.

McCraw said if the storm stalls after landfall as expected, heavy rains and ensuing tornadoes could affect 80 counties and 11 million residents.

The Beaumont-Port Arthur area has a large number of petrochemical and chemical plants. McCraw said companies worked with state officials to shut down and secure facilities, but not all are shuttered.

"Some plants need to stay open," he said, declining to provide details. "They're vital to national security."

Texas disaster officials warned that during Rita's fullest impact there will be little that can be done. But Jack Colley, state coordinator for the Governor's Division of Emergency Management, said the state was taking advantage of the last few hours before the winds became too strong to move food and water into the Houston area.

"Fully prepared"

"We are fully prepared for Hurricane Rita to strike this Texas coast," Colley said.

Colley also said it would be up to local officials to tell people when they can return to their homes. "That is at the discretion of local elected officials," he said. "The same elected officials who can order mandatory evacuations can decide when to let people back in."

Texas has called up more than half of its 20,000 National Guard troops. About 5,800 Texas National Guardsmen are deployed overseas.

Texas and Louisiana also have asked for a total of 25,000 active-duty troops, but a spokesman for Joint Task Force Rita said specific active-duty units had not been identified. Army Lt. Gen. Robert Clark, head of Joint Task Force Rita, based at Fort Sam Houston in San Antonio, said military units were ready to move in as soon as conditions allow today.

The task force's first priority will be search-and-rescue missions, particularly by air and executed by military as well as private aircraft.

Hotels and shelters in Dallas were at or near capacity. All Red Cross shelters were full, with 2,700 people housed in the convention center, Reunion Arena and three other facilities in the area. The city was housing evacuees at a former jail, which also was full.

In Lake Charles, La., the city was almost empty as thousands fled in advance of Rita.

"There's nothing really to compare to this," said Sgt. Wendell Carroll of the Calcasieu Parish Sheriff's Office in Lake Charles. "After Katrina, everybody's thinking about hurricanes has changed. At least now, hurricanes are being taken more seriously. We're ready and waiting."

The approach of Rita also has put a huge strain on Lafayette, La., a center of Cajun culture, where emergency officials scrambled to send Katrina evacuees to shelters farther north to clear space for the onslaught of Rita evacuees.

Lt. Gen. Russel Honore, the federal Katrina chief overseeing Rita preparation efforts from Lafayette, said hundreds of troops are staging in Baton Rouge but trucks and helicopters would not begin going into damaged areas until winds diminish to less than 40 mph.

"Pray," Honore advised the residents of southwest Louisiana. "A little prayer right now will work, hopefully."

Reuters provided information on the Galveston fire.