Hurricane Maria is now moving away from the Turks and Caicos Islands as a powerful Category 3 storm.
The U.S. National Hurricane Center says Maria still has maximum sustained winds of 125 mph (205 kph). The core of the storm was about 90 miles (145 kilometers) north of Grand Turk Island at 2 p.m. Friday afternoon.
Maria is moving to the north-northwest at 9 mph (15 kph) and the storm is expected to slowly weaken while making a turn toward the north by late Saturday. Forecasters in the Miami center say Maria's fierce core is expected to move away from the Turks and Caicos Islands in coming hours and move to the northeast and east of the Bahamas over the weekend.
Tropical storm conditions are possible in the central Bahamas beginning late Friday.
The National Weather Service says the Guajataca (wa ha TA ca) Dam is failing in western Puerto Rico and buses are evacuating people "as quickly as they can."
The government called the situation "extremely dangerous."
The weather service office in San Juan says dam operators reported at 2:10 p.m. that the dam at the northern end of Lake Guajataca in the northwest corner of Puerto Rico was failing and causing flash flooding downstream.
Emergency responders are reporting at least 110 homes have been destroyed by floodwaters in different communities around the Dominican Republic.
Juan Manuel Mendez, an emergency operations chief, says at least 18,500 evacuees are being kept from their homes while waiting for floodwaters to subside.
Authorities say rivers overflowed and debris carried along by the floodwaters destroyed four bridges and have cut off 78 small communities on the island.
"The river caught us by surprise," said Maria Acosta, a mother of three who used a bucket to try to remove mud that washed into her home in El Seibo, in the eastern part of the nation.