— PORT-AU-PRINCE, Haiti (AP) — Tropical Storm Isaac swept across Haiti's southern peninsula early Saturday, dousing a capital city prone to flooding and areas of the poor nation still trying to recover from the terrible 2010 earthquake.

The storm was heading toward eastern Cuba and forecasters said it poses a threat to Florida just as the Republican Party gathers for its national convention in Tampa. The U.S. National Hurricane Center in Miami said a hurricane warning is in effect for the Florida Keys and for the west coast of Florida from Bonita Beach south to Florida Bay.

Rocks, mud and other debris littered the streets of Port-au-Prince Saturday morning and the city was on high alert for potential flooding. But the worst of the storm has hit far from the capital.

At least two people died, a woman and a child, in the town of Souvenance, Sen. Francisco Delacruz told a local radio station.

Forecasters said Isaac could dump as much as eight to 12 inches (30 centimeters) and even up to 20 inches (51 centimeters) on Hispaniola, which is shared by Haiti and the Dominican Republic, as well as produce a storm surge of up to 3 feet (0.9 meters).

Government and international aid groups in Haiti's capital had been prepared to evacuate several thousand people from settlement camps that sprang up after the 2010 earthquake. But the main threat appeared aimed at Les Cayes, a city of about 45,000 people on the southwestern coast that is prone to flooding during heavy rain.

Isaac was centered about 95 miles (150 kilometers) east-southeast of Guantanamo Bay, Cuba, early Saturday, with maximum sustained winds of 60 mph (95 kph). It was moving northwest at 14 mph (22 kph). Tropical force winds extended nearly 200 miles (321 kilometers) from the storm's center.

Forecasters said the storm was likely to march up the Gulf of Mexico, offshore of Florida's west coast, as a hurricane on Monday, just as the Republican National Convention is scheduled to start. Tampa was within the storm's possible strike zone, but the most likely course would carry it toward landfall on the Florida Panhandle late Tuesday or early Wednesday.

Cuba declared a state of alert Friday for six eastern provinces, according to a Civil Defense announcement read on the afternoon news, and five central provinces were put on preliminary watch. Vacationers in tourist installations of those regions were evacuated.

Radio Baracoa, from the city of Baracoa on the northern coast of eastern Cuba, reported that high seas began topping the city's seawall Friday night. Reports said lower than normal rains had left reservoirs well below capacity and in good shape to absorb runoff.

Cuba has a highly organized civil defense system that goes door-to-door to enforce evacuations of at-risk areas, largely averting casualties from storms even when they cause major flooding and significant damage to crops.

In Port-au-Prince, a city of some 3 million ringed by mountains, authorities and aid workers tried to evacuate people from a tent camp to temporary shelters.

More than a hundred people were at a shelter in a school that President Michel Martelly toured Friday, but after the visit some people began to leave.

"They dragged me from the camp and brought me here," 38-year-old Marlene Charles, thirsty and hungry, said about the aid groups. "There's no way I'm going to spend the night here."

In the Dominican Republic, authorities evacuated people from low-lying areas but, as in Haiti, they encountered resistance. Still, authorities said they evacuated nearly 2,900 people. The majority were transferred to the homes of relatives while about 300 were sent to government shelters.

Flooding was reported in Santo Domingo and Santiago but no reports of injuries.

Organizers of next week's Republican National Convention in Tampa were monitoring storm developments, and authorities said there were no plans to cancel the convention.

Out in the eastern Atlantic, former Tropical Storm Joyce degenerated into a weak low pressure system Friday.