CASTRIES, St. Lucia (AP) -- Fast-moving Tropical Storm Chantal raced toward the small islands of the Lesser Antilles on Tuesday, with residents of St. Lucia shuttering schools and preparing to close the island's two airports as it neared.
The storm was centered about 45 miles (70 kilometers) north-northwest of Barbados around 8 a.m. EDT Tuesday, the U.S. National Hurricane Center in Miami said. The storm had maximum sustained winds near 50 mph (85 kph), and was moving west-northwest at 26 mph (43 kph).
Chantal was expected to move over the small islands on the eastern rim of the Caribbean early Tuesday and be near the Dominican Republic on Wednesday, according to the Hurricane Center.
Chantal could be near hurricane strength before it reaches Hispaniola, the island shared by the Dominican Republic and Haiti. Both countries are very vulnerable to flooding and landslides from storms, but widespread deforestation and ramshackle housing in Haiti mean even moderate rains pose a significant threat.
U.S. forecasters expect that wind shear and interaction with the mountains of Hispaniola and Cuba will cause Chantal to start weakening in about three days and it is expected to be a tropical depression Friday while over the Bahamas.
In St. Lucia's capital of Castries, supermarkets stayed open late Monday as islanders stocked up on emergency supplies including water and batteries.
The government was taking no chances earlier in the day, ordering a midday closure of all schools until Wednesday. The director of the local meteorological office warned that parts of the island could potentially be affected by landslides and flooding.
In a national address Monday evening, Prime Minister Kenny Anthony urged people to hunker down at home until the tropical storm had passed.
A tropical storm warning is in effect for St. Lucia, Barbados, Dominica, Martinique, Guadeloupe, Puerto Rico and the southern coast of the Dominican Republic from Cabo Engano to the border with Haiti.
A tropical storm watch is in effect for Haiti, the Turks and Caicos, the southeastern Bahamas, St. Vincent, the U.S. Virgin Islands, Vieques and Culebra, and the northern coast of the Dominican Republic from west of Cabo Frances Viejo to its border with Haiti.
In Barbados, officials urged people to stay tuned to radio stations and prepare for the rapid approach of Chantal, the Atlantic hurricane season's third named storm.
"This is hurricane season so we urge Barbadians to be prepared," said Kerry Hinds, deputy director of the island's emergency management department.
In Puerto Rico and the U.S. Virgin Islands, the U.S. Coast Guard urged all waterfront facilities to remove unsecured debris, hazardous material and pollutants from dockside areas. Pleasure craft operators were advised to seek safe harbor and secure their vessels.
The storm was expected to produce rain and strong winds in Puerto Rico, with gusts of up to 60 mph (96 kph) in southern and mountainous areas, according to Roberto Garcia, director of the National Weather Service on the island of less than 4 million inhabitants. Chantal was expected to pass more than 100 miles (160 kilometers) south of Puerto Rico early Wednesday.
AP writer David McFadden contributed to this report from Kingston, Jamaica.