PIEDRA BLANCA, Dominican Republic — Tropical Storm Noel buffeted south Florida with high surf and winds as it swirled slowly toward the Bahamas today after triggering mudslides and floods in the Caribbean that killed at least 81 people.

Forecasters warned of worsening storm conditions in the Bahamas later in the day, and the government issued a hurricane watch for the northwestern parts of the archipelago. On Andros Island, the chain’s largest, boat owners tied their vessels down ahead of the storm.

The U.S. National Hurricane Center today issued a tropical storm warning for the southeastern Florida coast from Ocean Reef to Deerfield Beach. A tropical storm watch was in effect from north of Deerfield Beach to Jupiter Inlet. A warning means tropical storm conditions are expected within 24 hours while a watch means such conditions are possible within that area.

The deadly storm dumped rains on the Dominican Republic and Haiti last night, more than two days after it struck the island of Hispaniola, where rescuers were struggling to reach communities cut off by flooding.

As they did, they found a rising toll of death and damage — at least 56 dead in the Dominican Republic, 24 in neighboring Haiti, and one in Jamaica.

Two days after a swollen river swept away the hamlet of Piedra Blanca in central Dominican Republic, Charo Vidal described climbing into a tree and watching her neighbor struggle to do the same, clutching infant twins while the waters swept an older daughter away.

“She couldn’t take care of all three,” Mr. Vidal said. “That is something very profound, to have a child snatched from your hands and you cannot do anything for them.”

“The river tore her from my hands as I held her,” said the mother, Mary De Leon.

At least seven people died in Piedra Blanca, emergency officials said.

President Fernandez of the Dominican Republic declared a 30-day state of emergency and asked for international help, especially rescue teams and helicopters. He also ordered residents to evacuate from dozens of potential flood zones.

At least 58,300 Dominicans fled their homes, some 14,500 of which were damaged, the head of the Emergencies Commission, Luis Antonio Luna, said. He said at least 56 people had died in the Dominican Republic so far.

Mr. Luna said officials were trying to reach dozens of isolated communities, but bad weather, a lack of helicopters, and damage to bridges and highways slowed rescue efforts. He said at least 27 people were reported missing.

In neighboring Haiti, floods rushed through the capital’s Cite Soleil slum, carrying away a 3-year-old boy. Two people were killed when their house collapsed in a mudslide in the hillside suburb of Petionville, and at least three others died in Jacmel.