Gustav was expected to make landfall before midday as a Category 3 hurricane, but its outer bands were already hitting the Gulf coast early on Monday.

An estimated 1.9 million people had fled coastal areas as Hurricane Gustav, officials said. This in one of the biggest evacuations in US history. More than 11 million residents in five US states were threatened by the fast-moving storm.

Oil companies shutdown nearly all production in the energy-rich Gulf of Mexico, a region that normally pumps a quarter of US oil output and 15 per cent of its natural gas.

But Gustav failed to draw as much power as once feared as it rolled across warm Gulf of Mexico waters. Forecasters said it was unlikely to grow stronger now and would begin to weaken as it moves inland.
The eye of the storm was on track to hit west of New Orleans, sparing the city a direct hit from the worst of its gusting winds.

But the US National Hurricane Center said Gustav was still likely toss up “an extremely dangerous storm surge” of up to 14 feet that could test the holding power of rebuilt levees that failed during Hurricane Katrina.

By Sunday night, the streets of New Orleans were ghostly quiet after some 95 per cent of the city’s population responded to desperate calls by officials for a sweeping evacuation.

Only 10,000 people were believed to have stayed behind in New Orleans. Police and several thousand national guard troops patrolled the empty city as a curfew went into effect in a bid to prevent looting.

On Monday morning, Gustav was packing maximum sustained winds of 115 mph, making it a Category 3 storm on the five-step Saffir-Simpson scale.

It was expected to swamp parts of Louisiana, Mississippi, Arkansas and Texas with up to 12 inches of rain and 20 inches  in some small areas. Isolated tornadoes, officials said.

Bush skips convention

President George W Bush, who was criticised for the slow relief efforts after Hurricane Katrina, cancelled his appearance at the Republican convention as scheduled instead a visit to Texas on Monday to oversee emergency response effort.

Flights from New Orleans and Gulf Coast cities were cancelled as the storm bore down on the region.