HOUSTON, September 12 – Hundreds of thousands of people have fled Houston, Texas, the fourth largest US city, as officials warned that those who stay behind in some coastal areas "face certain death" from Hurricane Ike’s wrath.,
"All neighbourhoods and possibly entire coastal communities will be inundated during the period of peak storm tide," the NHC said of land along Galveston Bay late Thursday ahead of the storm’s expected landfall late Friday or early Saturday.
"Persons not heeding evacuation orders in single family one- or two-story homes will face certain death," it said, as it forecast a storm surge as high as 22 feet (6.5 meters).
Galveston Bay stretches 25 miles (40 kilometres) inland towards Houston, whose suburbs reach the bay’s coast.
Texas governor Rick Perry also issued an urgent and ominous warning.
"My message to Texans in the projected impact area is this: finish your preparations because Ike is dangerous and he’s on his way," Perry said.
Authorities in Harris County, the jurisdiction encompassing Houston, said evacuations of the city’s most flood-prone areas, home to about a quarter million residents, began at 1700 GMT.
Forecasters said Ike, which left more than 100 dead across the Caribbean, likely would barrel ashore packing winds in excess of 120 miles (190 kilometres) per hour.
An updated track showed the storm making virtually a direct hit on the port city of Galveston and then Houston, a city of 2.2 million people, and with a metropolitan area topping 5.6 million.
Texas Lieutenant Governor David Dewhurst told CNN Thursday that a mass mobilization was well underway.
"We have been moving supplies and moving buses now for four days," he said. "We have moved C-130s (transport planes) and ambulances. We have 1,350 buses we have moved into the area."
Officials said the evacuations began with the elderly, infirm and other residents with special needs. Houston officials planned to re-route highway traffic and said fueling stations would be placed on major roads to facilitate the exodus.
The NHC made its dire warning about Galveston Bay after it had become clear that some residents in Galveston resisted the order to clear out, despite warnings that the entire island on which the city is located could be inundated.
"Unless it’s really bad, we don’t want to go anywhere," said resident Leslie LeGrande.
Alicia Cahill, a public information officer for Galveston, expressed worry that some people were staying on the island.
"There’s more people here than I would have thought," she said.
Historical data listed by the NHC justifies Cahill’s concern. The centre lists the "Great Storm" of 1900, which slammed Galveston, as the deadliest hurricane in US history, killing at least 8,000 people.
South of Galveston in Freeport, evacuations had cleared out most of the coastal town, with fewer than 20 percent of residents remaining Thursday, although some still planned to ride out Ike’s wrath, a local TV station reported.
At 0300 GMT Friday the National Hurricane Centre in Miami said the storm had maximum sustained winds of around 100 miles (160 kilometres) per hour, making it a Category Two storm on the five-level Simpson-Saffir scale.
The centre said Ike was located about 340 miles (545 kilometres) southeast of Galveston and was moving west-northwest at 12 miles (19 kilometres) per hour.
"Ike is forecast to become a major hurricane prior to reaching the coastline," the centre said, adding that "weather will deteriorate along the coastline long before the center reaches the coast."
Tropical storm-force winds were already being felt late Thursday east of Texas in Louisiana, a state keeping a wary eye on Ike just two weeks after the city of New Orleans and the Louisiana coast was hammered by Hurricane Gustav.
Oil and natural gas production in the Gulf of Mexico was largely shut off, though the US Department of Energy said Ike appeared likely to spare most rigs and platforms there.
"Current projections show it missing most of the gulf’s oil and gas installations and hitting the Texas coastline sometime late tomorrow (Friday)," the department said in a statement.
"Some 95.9 percent of the Gulf of Mexico’s 1.3 million barrels per day of oil production and 73.1 percent of its 7.4 billion cubic feet per day of natural gas production has been turned off," it said.
The bulk of US oil refineries are in the gulf, and Anglo-Dutch oil giant Shell had evacuated personnel from its offshore installations as of Wednesday.