The growing storm, with 90 mph (145 kph) winds, also pounded nearby Grenada, where residents were still trying to rebuild from the devastation of Hurricane Ivan last September.
In energy-rich Trinidad and Tobago, rivers in the capital, Port of Spain, and in central Trinidad, broke their banks as Emily dropped up to 8 inches (20 cm) of rain along its path through the Windward Islands.
"At this point, we are flooded out by reports of flood all over the place," said Myron Chin, director of the Office of Disaster Preparedness and Management. No injuries were reported.
At 8 a.m. EDT (1200 GMT), the center of Emily was about 85 miles (137 km) west-northwest of Grenada and moving to the west-northwest at about 18 mph (29 kph), the U.S. National Hurricane Center in Miami said.
Emily blossomed quickly on Wednesday from a tropical storm into a hurricane and forecasters said they expected it to strengthen further in the next day or so.
The hurricane center's long-range forecast had Emily racing across the Caribbean Sea north of the Netherlands Antilles over the next two days. It would skirt Jamaica's south coast on Saturday and hit Mexico's Yucatan peninsula late on Sunday.
Emily's passage near Grenada piled on the misery for the 90,000 residents of the spice island, where Ivan caused about $2.2 billion in damage last September, more than double Grenada's annual economic output.
The storm damaged or destroyed 90 percent of the housing stock and many people are still doing repairs.
Storm warnings were in effect for the Dutch islands of Aruba, Bonaire and Curacao and the northern coast of Venezuela from Pedernales to Punto Fijo.
Venezuela's oil operations were unscathed as the storm passed to the north, oil officials and shipping sources said.
BP continued working to right its $1 billion Thunder Horse platform, which had been discovered listing after Hurricane Dennis passed through the Gulf of Mexico last weekend. Emily, however, was not forecast to venture near the area.
Forecasters said a tropical storm watch could be issued later on Thursday for the south coast of Hispaniola, the island shared by Haiti and the Dominican Republic.
Hurricane Dennis killed at least 44 people in Haiti last week during a trek through the Caribbean and the Gulf of Mexico in which more than 70 people died. The toll included 16 in Cuba, one in Jamaica and ten in the United States.
- Reuters - Thomson Reuters Foundation
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