Catastrophic storm surge forecast as governors issue mandatory evacuation orders to 620,000 people.
Forecasters in the United States say Hurricane Laura could hit the coasts of Louisiana and Texas with “unsurvivable” storm surges.
Currently a Category 4 storm, Laura has rapidly picked up speed, driven by the warm waters of the Gulf of Mexico.
Half a million people have already been forced to leave their homes.
Tens of millions more face potential devastation.
Al Jazeera’s Andy Gallacher reports.