Carlos Medellin-Guillen, 36, died on Tuesday in Louisiana when he fell 18 feet from a tree he had climbed, the Associated Press reports.
His death was the first Louisiana fatality attributed to Isaac, which was then still a tropical storm.
According to the AP, Medellin-Guillen lived in Erath, a town of 2,100 in Vermilion Parish.
The Associated Press is separately reporting the death of a tow truck driver in Picayune, Miss., who died on Thursday morning when his truck was struck by a fallen tree. His name has not yet been released.
Isaac was responsible for at least 29 deaths in Haiti and the Dominican Republic when the tropical storm passed over the islands last weekend.
Isaac, which was downgraded from a hurricane to a tropical storm on Wednesday, has left nearly half of all electrical customers in Louisiana without power, according to the AP. About 150,000 customers in Mississippi are also without power.
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