More than 500,000 people are under evacuation orders in parts of Texas and Louisiana as Hurricane Laura is predicted to make landfall, bringing destruction to the US Gulf Coast.

“These numbers are unimaginable, to think that there will be a wall of water over two storeys high coming on shore, is very difficult for most to conceive,” Benjamin Schott, the chief meteorologist for New Orleans, Louisiana, said during a press conference on Wednesday

Mr Schott said some neighbourhoods will be “unrecognisable”.

Unsurvivable storm surge with large and destructive waves will cause catastrophic damage from Sea Rim State Park, Texas, to Intracoastal City, Louisiana, including Calcasieu and Sabine Lakes. This surge could penetrate up to 30 miles inland from the immediate coastline. #Laura pic.twitter.com/bV4jzT3Chd

— National Hurricane Center (@NHC_Atlantic) August 26, 2020

In a Wednesday update the National Hurricane Center said Laura will cause an “unsurvivable storm surge and destructive waves” bringing “catastrophic damage” to more than 200 kilometres of coast from eastern Texas to central Louisiana.

Louisiana National Guard Sgt. Aaron Dugas prepares a boat for the arrival of Hurricane Laura. Photo: Getty

The surge of water, with some waves reaching over 4 metres, has the potential to penetrate nearly 50 kilometres in the coastal flatlands, causing major damage to urban areas.

Evan Raggio and other people purchase supplies at the Stine hardware store before the possible arrival of Hurricane Laura. Photo: Getty

“We are very concerned that not enough people are evacuating,” Nic Hunter, the mayor of Lake Charles, a city in Louisiana, told public radio on Wednesday.

“This is a last-ditch effort over the next hour, hour and a half for people to try and get out of town.”

Shawn Nelson, 7, right, and Asia Nelson, 6, left, board a bus to evacuate Lake Charles, Louisiana. Photo: AAP

Hurricane Laura is forecasted to “rapidly strengthen” on Wednesday reaching an extremely dangerous category 4 level before making landfall and bringing ferocious winds, the National Hurricane Center said in a Wednesday update.