A particularly vivid paragraph from a Times-Picayune article at NOLA.com:

About 5 p.m., almost as if on cue, the battery power of all the house alarms in the neighborhood seemed to reach a critical level, and they all went off, making it sound as if the area was under an air-raid warning. Two men surviving on generator power in the Lake Terrace neighborhood near the Lake Pontchartrain levee still had a dry house, but they were watching the rising water in the yard nervously. They were planning to head out to retrieve a vast stash of beer, champagne and hard liquor they found washed onto the levee. As night fell, the sirens of house alarms finally fell silent, and the air filled with a different, deafening and unfamiliar sound: the extraordinary din of thousands of croaking frogs.