Isaac now a Category 1 hurricane
According to an updated statement from the National Hurricane Center, issued at 12:20 p.m. ET, reports from an Air Force craft indicate Isaac’s winds have surpassed the 74-mph threshold necessary to classify a storm as a hurricane.
The storm remained about 160 miles southeast of New Orleans and was moving northwest at about 10 mph, according to the updated statement.
The central pressure had lowered to 975 mb, slightly below the 11 a.m. ET reading of 976 mb. Lower pressure means stronger winds.
Flooding is the greatest threat, with torrential rain and storm surges set to smash Louisiana and Mississippi and east to Alabama and the Florida Panhandle.
Rain from the outer bands is falling on New Orleans and coastal cities, with the center of the storm forecast to reach land late this evening or overnight.
CNN contributed to this report.