PORT-AU-PRINCE, Haiti -- Gustav stalled offshore Wednesday and poured more misery onto Haiti after landslides and flooding killed 22 people. Oil workers began leaving their rigs and New Orleans drew up evacuation plans as forecasters warned the storm could plow into the U.S. Gulf coast as a major hurricane.

Gustav was dumping 12 inches (30 centimeters) or more of rain on Haiti’s deforested southwestern peninsula, after killing 14 people in Haiti and an eight-member family in the Dominican Republic. It was creeping toward the warm Caribbean waters between Cuba and Jamaica, where it was expected to be reborn as a hurricane as early as Thursday.

Gustav’s expected track pointed directly at the Cayman Islands, an offshore banking center where residents boarded up homes and stocked up on emergency supplies. By Labor Day, Gustav could make landfall anywhere from south Texas to the Florida panhandle, and hurricane experts said everyone in between should be concerned.

“We know it’s going to head into the Gulf. After that, we’re not sure,” said meteorologist Rebecca Waddington at the National Hurricane Center in Miami. “For that reason, everyone in the Gulf needs to be monitoring the storm. At that point, we’re expecting it to be a Category 2 hurricane.”

New Orleans officials began planning a possible mandatory evacuation, hoping to prevent the chaos they saw after Hurricane Katrina struck three years ago Friday. Mayor Ray Nagin left the Democratic National Convention in Denver to help the city prepare.

Oil prices spiked more than $2 to above $118 a barrel, rising for a third day on fears that Gustav—like Katrina and Rita three years ago—could damage the Gulf Coast energy infrastructure, home to 15 percent of the nation’s natural gas output, a quarter of its oil production and nearly half its refining capacity.

Royal Dutch Shell PLC said it was evacuating 300 people from rigs Wednesday, and other producers were doing the same. Transocean Inc., the world’s largest offshore drilling contractor, said all 11 of its Gulf rigs were pulling up and securing drill pipe and other underwater equipment as a precaution. It too was evacuating workers.

Any damage to the oil infrastructure could send U.S. pump prices spiking, possibly before the busy Labor Day weekend.

“A bad storm churning in the Gulf could be a nightmare scenario,” said Phil Flynn, an analyst at Alaron Trading Corp. in Chicago. “We might see oil prices spike $5 to $8 if it really rips into platforms.”

Gustav is particularly worrisome because there are few surrounding wind currents capable of shearing off the top of the storm and diminishing its power, the hurricane center said.  “Combined with the deep warm waters, rapid intensification could occur in a couple of days.”

On Wednesday, Gustav had top winds of 50 mph (81 kph) and was centered 90 miles (145 kms) south-southeast of Guantanamo, crawling west-northwest at 3 mph (5 kph).

A hurricane warning was in effect for parts of Cuba, including the U.S. military base at Guantanamo Bay, where base spokesman Bruce Lloyd predicted “a really wet night.”

Nearly 30,000 people were evacuated from low-lying areas in eastern Cuba, and state television showed muddy, waist-high water damaging homes. Fidel Castro pledged in an essay that “no one will be forgotten” by the government.

The government of the Cayman Islands ordered people to secure loose materials in their yards to prevent them from becoming missiles in high winds, and told them to stock up on food, medicine and fuel for generators.

In the Haitian capital, the chocolate waters of a river spilled over its banks, lapping at shacks in the Cite Soleil slum.  Residents pushed bicycles and balanced boxes of belongings on their heads as they sought higher ground.

U.N. peacekeepers were preparing to evacuate residents from the western town of Jeremie even as rain continued to fall, U.N.  official Andre Pierre said.

Civil protection director Marie Alta Jean-Baptiste said 14 people were killed in mudslides and floods in Haiti, including a young girl swept off a bridge by flood waters.

In the Dominican Republic, a mother and six of her seven children—ranging in age from 11 months to 15 years—were killed when a landslide crushed their house. The body of Marcelina Feliz was found hugging that of her smallest child, rescue officials said. A neighbor was also killed.

“I don’t know how I can live now, because none of my family is left,” said Marino Borges, Feliz’s husband and father of several of her children.