Downgraded: Hurricane Rita drops to Category 4

HOUSTON, Texas – Forecasters downgraded Hurricane Rita to a Category 4 storm Thursday, but warned that it was still a powerful, and extremely dangerous storm.

At 2 p.m. ET, the storm had maximum sustained winds of 150 mph, the National Hurricane Center said.

The storm was centered about 435 miles southeast of Galveston, Texas, and was moving to the west-northwest at 9 mph . Forecasters expect Rita to make a gradual turn to the northwest during the next 24 to 36 hours.

Hundreds of thousands of people in Texas and Louisiana were loading up their cars and fleeing inland Thursday as Rita menaced the Gulf Coast.

Houston resident Tim Conklin told CNN that he had been in bumper-to-bumper traffic for 13 hours and had only gotten about 48 miles. He said the drive to Dallas, where his father-in-law lives, usually only takes about four hours.

On Highway 290, a major road between Houston and Austin, people were pushing their cars and minivans to save gas – and were moving just as fast as the vehicles that were driving. Others were stopped on the side of the highway after breaking down or running out of gas.

Texas Department of Transportation spokesman Mark Cross told CNN that this is the first time that a mandatory evacuation has been issued for Houston – a city of 3 million people. He said that traffic was being reversed on key roads leading into the city to speed the flow of traffic.

Gas stations along some of the major arteries out of Houston and Beaumont were running low on gas, said Steven McCraw, director of the governor's division of emergency management.

Texas Gov. Rick Perry said that gas trucks were being dispatched along the evacuation route to help people who are low on fuel.

There were also long lines of lines of frustrated travelers at Houston's George Bush Intercontinental Airport after about 100 employees of the Transportation Security Administration did not show up for work.

CNN correspondent Rick Sanchez, who was at the airport, said in one area he saw three screeners attempting to handling crowds that a team of a dozen or more screeners usually handle.

NEW FLOOD FEARS FOR NEW ORLEANS. Louisiana Gov. Kathleen Babineaux Blanco urged residents in Louisiana's coastal parishes to immediately evacuate northward.

"As you know, Rita took a turn to the east last night and southwest Louisiana is now in danger," Blanco said. "I'm urging everyone to evacuate now."

She said the state has buses in St. Charles and Lafayette to evacuate people. Heavy rain could hamper evacuation efforts Friday, she said.

Blanco urged people to avoid major highways, which are backed up with heavy traffic. Shelters have been set up in the northern part of the state, she said.

The center of the hurricane is expected to make landfall early Saturday between Galveston, Texas, and the Texas-Louisiana border.

The hurricane center said Thursday that Rita could dump as much as three inches of rain in the New Orleans area when it hits Gulf Coast – a threshold that the Army Corps of Engineers has said may overwhelm that city's fragile levee system.

"There is still a risk from New Orleans and eastward of upwards to about three inches of rain, at least that's the current projection," said Ed Rappaport, deputy director of the center.

Officials started closing the flood gates around Lake Pontchartrain Thursday morning in preparation for the Rita.

More than 1,000 deaths, most of those in Louisiana, are blamed on Katrina, which struck August 29.

RESIDENTS TAKE WARNINGS SERIOUSLY. Galveston Mayor Lyda Ann Thomas told CNN that at least 75 percent of the city's 58,000 residents had evacuated by Thursday morning.

"We hope that whoever is left here... will move on out today," Thomas said.

"We hope and pray that Hurricane Rita will not be a devastating storm, but we got to be ready for the worst," President Bush said in Washington.

Galveston was flattened by an infamous hurricane in 1900.

Some people leaving Texas cities this week were experiencing their second evacuation in a month, having fled Hurricane Katrina to Texas.

Corpus Christi Mayor Henry Garrett signed mandatory evacuation orders Wednesday for 250,000 people in that Texas coastal city and the rest of Nueces County. Garrett said the 13,000 to 15,000 residents of Padre and Mustang islands and low-lying areas of Corpus Christi must leave their homes by 2 p.m. central time Thursday. The rest have until Thursday evening to leave.

Garrett said he is ordering the evacuations at least a day earlier than he normally would because of the disaster wrought by Katrina.

R. David Paulison, acting undersecretary for homeland security, said support teams and supplies were being moved from Florida to Texas as Rita's landfall nears.

Fourteen urban search-and-rescue teams, with a total of 800 members, and 400 medical personnel were being put in place, he said.

He said the Department of Defense was helping to set up field hospitals to accommodate 2,500 beds, providing materials to build temporary bridges in case of serious damage to infrastructure, and organizing food kitchens. In addition, the Department of Transportation was providing buses for evacuations.

Hurricane-force winds were extending outward for up to 85 miles from the center, and tropical storm-force winds were extending up to 185 miles.

As Rita churned toward the coast, a hurricane warning was issued for Port O'Connor, Texas, to Morgan City, La. The warning means that hurricane conditions, including sustained winds of at least 74 mph, are possible within 24 hours.

A tropical storm warning was in effect on either side of the hurricane warning.

New Orleans and Lake Pontchartrain are covered under a tropical storm watch, which extends from the mouth of the Mississippi River to the Pearl River. That means tropical storm conditions are possible in the next 36 hours.

Several refineries, that process about 3 million barrels of oil each day, could be threatened by Rita. Some energy analysts predict that disruption from the storm could trigger a surge in gas prices.