Isaac turned into a full-blown category 1 hurricane today as it rolled over the Gulf of Mexico toward Louisiana, where residents in four states left boarded-up homes and New Orleans waited nervously behind flood-defence levees strengthened after the devastating Katrina struck exactly seven years ago.

Gustav slammed into Cuba’s tobacco-growing western tip as a monstrous Category 4 hurricane while both Cubans and Americans scrambled to flee the storm as it roared toward the oil-rich Gulf of Mexico and New Orleans.