Senior hurricane specialist Stacy Stewart tracks Isaac at the National Hurricane Center in Miami, Tuesday, Aug. 28, 2012. Forecasters at the National Hurricane Center warned that Isaac, especially if it strikes at high tide, could cause storm surges of up to 12 feet (3.6 meters) along the coasts of southeast Louisiana and Mississippi and up to 6 feet (1.8 meters) as far away as the Florida Panhandle. (AP Photo/Alan Diaz)