Winds began to pick up Friday afternoon in southeast Texas as the outer bands of Hurricane Rita, a massive Category 3 storm, reached coastal communities.
With the hurricane generating winds of tropical storm force extending 205 miles (335 kilometers) from the center, cities like Galveston were reporting winds of 47 mph (77 kph).
"We're seeing our first real rains, some of those bands coming in and affecting us," CNN's David Mattingly reported from Galveston. "It's not a lot of rain, but in typical Gulf storm fashion it's coming in sideways -- getting blown at us rather hard."
A key levee into the 9th Ward neighborhood, still almost empty after Hurricane Katrina's flooding.
"It's spreading rapidly down to the south-southeast, so they're going to have complete flooding in that area again," said Maj. Gen. Bill Caldwell, commander of the Army's 82nd Airborne Division, following a tour of the area Friday.
Caldwell, whose troops are aiding the relief effort, said floodwater had spread across 30 to 40 city blocks by noon.
Video showed water spilling through the break in the levee, quickly flooding both the 9th Ward and Lower 9th Ward, which are divided by the canal.
The levee system that protects the city was breached when Katrina came through August 29. More than 1,000 deaths along the Gulf Coast have been blamed on Katrina, most of them in Louisiana.
The 9 p.m. ET advisory from the National Hurricane Center placed Rita's center in the Gulf of Mexico about 85 miles (137 kilometers) southeast of Sabine Pass on the Texas-Louisiana border. It was moving northwest at about 11 mph (18 kph).
The storm's maximum sustained winds were 120 mph (193 kph), making it a Category 3 storm.
The latest projections showed Rita making landfall early Saturday near Port Arthur, Texas. The city of about 58,000 people is home to a port and several oil refineries and chemical plants, according to the chamber of commerce's Web site.
A hurricane warning was in effect from Sargent, Texas, to Morgan City, Louisiana, meaning hurricane conditions such as sustained winds of at least 74 mph (118 kph) are possible within 24 hours.
Texas Gov. Rick Perry told reporters more than 2 million people in his state had evacuated, and he assured citizens that "we're going to get through this."
A bus carrying about 45 elderly evacuees burst into flames on Interstate 45 south of Dallas, killing as many as 24 people. It pulled over and people were getting off when a series of explosions ripped through the bus, said Dallas County Sheriff's Sgt. Don Peritz.
Peritz said the fire was believed to have started in the bus's brake system and may have caused oxygen canisters on the bus to explode.
Ed Rappaport, deputy director of the National Hurricane Center in Miami, Florida, said the center of storm, packing the most powerful winds, should come ashore Saturday morning near daybreak.
"We still think that the storm will make landfall on the upper Texas coast, potentially as far east as southwestern Louisiana," he said, noting the storm could still shift south toward the Galveston-Houston area.
Prior to a visit to the U.S. Northern Command in Colorado, which is supporting federal disaster relief efforts, President Bush stopped at the Federal Emergency Management Agency in Washington.
"Our job is to assist" state and local governments, he said. "We will make sure that my entourage does not get in the way of people doing their job," he said.
The acting director of FEMA sought to reassure the nation that the agency learned lessons from Katrina.
David Paulison told reporters the agency was working round the clock to coordinate relief efforts with local and state governments to meet their needs.
He said 17 urban search and rescue teams comprising 900 people were already in Texas; another 400 rescuers were standing by in Louisiana.
He urged residents to heed the advice of local authorities.
"I know how difficult it's going to be after the storm. It's going to be a few days before the first responders can get in there," Paulison said. "So, please stay where you are, stay in a safe location and do not return to your home until authorities say it's safe to do so."
As skies darkened, authorities told residents who had not fled to look instead for secure shelter. "We're telling people to stay in place," said Houston Police Chief Harold Hurtt.
The Houston Astrodome, recently a shelter for thousands of Katrina evacuees, was being used Friday as a staging ground for first responders, with hundreds of ambulances, fire engines and other emergency vehicles set to respond to anything the storm brings.
Near Lufkin, Texas, many evacuees were stranded on the side of the road, stuck without fuel and unsure what to do next.
Jennice Hall told CNN she and 11 other family members in three cars may have to ride out the storm in their vehicles if relatives from north Texas don't reach them in time.