The Gulf of Mexico oil spill could grow even more disastrous if the looming hurricane season churns up towering black waves and blasts beaches and crowded cities with oil-soaked gusts, experts warned.

With just three weeks before the Atlantic hurricane season lurches into action, odds are more than 40 per cent that a big storm could cross the giant spill gushing from beneath a ruptured well on the seabed.

An April 20 blast sank the Deepwater Horizon offshore drilling platform, killing 11 workers and leaving its uncontrolled well to gush millions of gallons of oil into the gulf waters.

Multiple tornadoes killed at least five people on Monday in the central US state of Oklahoma, the Oklahoman daily said on its website.

The Oklahoma Emergency Management Department said there were injuries from the severe storms and tornadoes they spawned statewide, but offered no numbers.

In Oklahoma City, tornadoes ripped through the metro area tossing cars and flipping mobile homes, leaving several neighbourhoods heavily damaged, the daily said. The OG&E power company reported 31,000 outages from the storm, including 28,000 in Oklahoma City.

Last month, forecasters who issue a closely watched Colorado State University seasonal forecast said there was a 44 per cent chance a hurricane would enter the Gulf of Mexico in the next few months, far greater than the 30 per cent historic average.

"The high winds may distribute oil over a wide area," said National Hurricane Centre meteorologist Dennis Feltgen. What's more "storm surges may carry oil inland, mixed with hurricane debris," he added, presumably with environmental consequences.

The movement of the oil would depend much on the track of the hurricane, according to Mr Feltgen, who said a hurricane passing to the west of the oil slick could drive a large volume of oil to the fragile coastline.

Yet "high winds and seas will mix and 'weather' the oil, which helps accelerate the biodegradation process," he noted.