Some south Texas areas began taking precautions as Category 4 Hurricane Dean followed a course toward the Yucatan Peninsula and the Gulf of Mexico, with the Texas coast a possible target.

Residents of Brownsville were urged to voluntarily evacuate an area near the Mexico border on Sunday as a hurricane watch was issued for part of Mexico's Yucatan Peninsula.

Click here to track Hurricane Dean.

The Texas Youth Commission had started evacuating nearly 270 inmates and staff members from its Evins facility in Edinburg. They were being transferred to another facility 400 miles north in Brownwood, according to Gov. Rick Perry's office.

Parts of Texas were still cleaning up from the flooding caused by Tropical Storm Erin last week, and remnants of that weather system inundated Oklahoma on Sunday, flooding homes and roads and blacking out thousands of customers, mostly in the Oklahoma City area.

One Oklahoma woman drowned in her flooded basement early Sunday and a motorist was missing after a vehicle was washed off a road, local and state officials said.

A decision to leave ahead of any signs of Dean was tough for many in the coastal city of Galveston, where residents remember the disastrous evacuation before Hurricane Rita in 2005. State officials say they've worked out the kinks in the system, but many Galveston residents aren't ready to believe them.

"I've talked to a lot of people about this," said resident Chuck Lee. "They'd rather die in their homes than die in their cars on some highway."

The Rita evacuation quickly turned into a disaster, as motorists from the coast ran into residents fleeing Houston, clogging evacuation routes for miles in sweltering heat. Gas stations closed after running out of fuel and supplies and motorists sat stranded and helpless for hours.

People also were preparing in New Orleans, where the memory of Hurricane Katrina is still fresh.

Patrice Garibaldi said her family was beginning to pack things they might need if they left the city and put things they'd leave behind higher. The family has rebuilt a house in eastern New Orleans, and Garibaldi said the threat of Dean was nerve-racking.

"I pray it doesn't come," she said, but her family is preparing because she's not satisfied the levees will be able to withstand a strong storm.

President Bush signed a pre-landfall emergency disaster declaration for Texas, allowing federal equipment and supplies to be moved in now, White House spokesman Gordon Johndroe said.

Nearly 25,000 customers of Oklahoma Gas and Electric still had no power by midday Sunday because of that state's storm, the utility reported.

Some injuries were reported in Blaine County, Okla., where flooding damaged homes and buildings in Watonga and Geary, said Blaine County Emergency Management Director Janell Wood. The rain collapsed the roof of a nursing home in Geary, but no injuries were reported, Wood said.

Wind gusted to 82 mph at Watonga, Okla., destroying some mobile homes, authorities said.

"It was quite a night," Watonga Police Chief Gary Clyden told KWTV television. "This was a bad boy. The rain was straight horizontal, and the wind was just awesome."

Erin's aftermath in Texas also includes efforts to save an infant dwarf sperm whale. The 50-pound, weeks-old whale and its ailing mother were found on a Galveston beach last week as the tropical storm's waves lashed the island.

The mother died Saturday and rescuers were feeding the calf, dubbed "Moby," through a tube in a rehabilitation tank at a National Oceanic and Atmospheric Administration facility, said Heidi Watts, operations coordinator for the Texas Marine Mammal Stranding Network.