The National Hurricane Centre in the United States has warned residents of Galveston, Texas, living in homes higher than a single storey that they "face certain death" if they do not flee before Hurricane Ike comes ashore from the Gulf of Mexico.

Across wide areas of coastal Texas, hundreds of thousands of people have been taking heed of the advice of emergency officials to leave their homes for safety further inland.

Hurricane Ike is generating winds of 160 kilometres an hour, and is growing in strength as it crosses the Gulf of Mexico.

"All neighbourhoods and possibly entire coastal communities will be inundated during the period of peak storm tide," the National Hurricane Centre said in a statement.

"Persons not heeding evacuation orders in single family one or two-storey homes will face certain death."

Texans, mindful of the devastation caused to the Gulf Coast by Hurricane Katrina in 2005, are not taking any chances with a storm which has already left 800,000 people in Haiti in urgent need of food and shelter.

"We're getting up out of here," said Nykera Allen, a Galveston student who was loading up her car to drive to San Antonio in central Texas.

"They're going to shut the lights and the water off and that's not a good situation."

The hurricane's current track would see it hit the Texas coast near Freeport in Brazoria County, just south of Galveston.

It could be the worst storm to hit the Texas coast since Hurricane Carla came ashore near Corpus Christi in 1961.

The coastal areas under threat from Ike are lined with oil refineries that process about 25 per cent of the nation's fuel.

Some stretches boast resorts and million-dollar beachfront homes.

Ike arrives just 10 days after Hurricane Gustav forced 2 million people to flee the Louisiana coast and threatened a New Orleans still reeling from Katrina's devastation.

"The most important message I can send is, do not take this storm lightly," US Homeland Security Secretary Michael Chertoff said in Washington.

"This is not a storm to gamble with."

-BBC/Reuters