The bodies of a man and woman were found in 7 feet of water at a home in Plaquemines Parish, Louisiana, which was hit hard by Isaac, officials said late Thursday.
An autopsy will be conducted to determine the cause of the death of the couple, described as in being their 40s, parish president Billy Nungesser told CNN. The two were found late Thursday afternoon in the dwelling's kitchen.
The house is on the parish's East Bank, said Commander Terry Rutherford of the Plaquemines Parish Sheriff's Office.
Officials in Mississippi earlier reported a storm-related death.
A tow truck driver attempting to clear debris on a road was struck and killed by a falling tree, officials said. The incident took place at midnight, said Amanda Harris, deputy director of the Pearl River County Emergency Management office. The National Weather Service said it received reports of the fatality in Picayune.
Weary residents in Louisiana and Mississippi, meanwhile, began moving into recovery mode Thursday as a weakened Isaac dumped additional rain during its slow trek northward.
Amid the flooding, there was good news: All coastal warnings were discontinued, utility workers were making progress and more roads were reopening.
Isaac, downgraded from a tropical storm to a tropical depression, was still causing problems, though.
CNN iReporter Gerard Braud had no water or power at his home in Mandeville, Louisiana, on the northern shores of Lake Pontchartrain.
"It comes to a point when the lake and your yard become one," he said of 36 hours of constant waves. Fortunately, water levels beneath his home, which is built on pilings, had dropped a few feet by Thursday night.