DELCAMBRE, La. (AP) – Laura has strengthened into a menacing Category 4 hurricane. The storm’s power is raising fears of a 20-foot storm surge that forecasters say would be “unsurvivable” and capable of sinking entire communities on the Texas and Louisiana coast. Authorities implored coastal residents to evacuate and worried that not enough had fled. The storm grew nearly 70% in power in just 24 hours to reach Category 3 status, and it continued to draw energy from the warm Gulf of Mexico waters. Laura was on track to arrive late Wednesday or early Thursday as the most powerful hurricane to strike the U.S. so far this year.