Tropical Storm Isaac dumped torrential rains on Haiti and the Dominican Republic and began its assault on eastern Cuba on Saturday.
Heavy rains and high winds lashed Haiti's southern coast, flooding parts of the capital Port-au-Prince and flattening tents in some of the fragile resettlement camps that house more than 350,000 survivors of the 2010 earthquake.
A 10-year-old girl was killed in Port au Prince when a wall fell on her, the Civil Protection authority said. Power outages and minor flooding were reported as Isaac moved across the hilly and severely deforested Caribbean country.
"We haven't had any power since the storm started yesterday. We passed the night with no sleep," said Magdala Jean-Baptiste, who huddled with her frightened children in their home in the southern coastal city of Jacmel.
In the Dominican Republic, Isaac felled power and phone lines and left at least a dozen towns cut off by flood waters. The most severe damage was reported along the south coast, including the capital Santo Domingo, where more than half the city was without power.
Rising winds and waves began whipping the eastern part of Cuba on Saturday afternoon, prompting government alerts for 11 provinces. In Cuba's easternmost city of Baracoa, water crashed over the seawall and rivulets ran through the nearby streets.