Gulf Coast residents braced for the arrival of Isaac, due to come ashore on the night of August 28, 2012. As of 10:00 a.m. Central Daylight Time on August 28, the U.S. National Hurricane Center (NHC) reported that a hurricane warning was in effect from Morgan City, Louisiana, eastward to the Mississippi-Alabama border, including the New Orleans metropolitan area. At the time of that bulletin, however, Isaac remained a tropical storm, with maximum sustained winds of 70 miles (110 kilometers) per hour.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image of Isaac over the Gulf of Mexico at 2:00 p.m. CDT on August 27, 2012. One hour earlier, the NHC reported that Isaac had winds of 65 miles (100 kilometers) per hour, and the storm was located about 280 miles (450 kilometers) southeast of the mouth of the Mississippi River.
As Isaac neared the Louisiana coast on August 28, the NHC warned of storm surges, which might combine with high tide to raise water levels by 6 to 12 feet (2 to 3.5 meters) in Mississippi and southeastern Louisiana. High water levels also threatened parts of Alabama and Florida. Other potential hazards included high winds, tornadoes, and heavy rains. The NHC warned that rainfall totals could range from 7 to 14 inches (18 to 36 centimeters), with isolated amounts as high as 20 inches (50 centimeters).