Storm Rafael has moved north of the Virgin Islands while dumping heavy rains around the eastern Caribbean.

The storm was centred about 105 miles (170 kilometres) northeast of St. Croix in the U.S. Virgin Islands at 2 a.m. EDT Sunday. Rafael had top sustained winds of 50 mph (85 kph) and was moving northward at 14 mph (22 kph).

The U.S. National Hurricane Center in Miami said the storm was expected to gain some strength and could become a hurricane by late Monday. Forecasters said the storm was on a northward trek and was expected to turn toward the north-northwest on Sunday as it moved away from the Virgin Islands.

As a result of the storm, Cape Air and regional carrier LIAT cancelled flights Saturday that had been scheduled to leave from Puerto Rico's main international airport. The Carnival Victory cruise ship also cancelled a stop in St. Maarten on Saturday.

Flooding was reported in the eastern Caribbean island of Trinidad, where the storm caused a brief power outage at the island's main international airport late Friday. At least one flight was cancelled. The hurricane centre said the storm's squalls and heavy rains were affecdting much of the Northern Leeward Islands early Sunday.