Hurricane Earl churned towards the North Carolina coast of the eastern U.S. seaboard on Tuesday after lashing Puerto Rico and the northeast Caribbean islands with winds, rain and waves, the U.S. National Hurricane Centre said.

The forecast track of Earl, the second major hurricane of the 2010 Atlantic season, showed the fringes of the powerful Category 4 storm clipping the barrier islands of North Carolina's Outer Banks early on Friday and threatening the densely populated coast northward from there to New England.

A hurricane watch could be posted by Tuesday night for the mid-Atlantic coast, alerting residents to expect storm conditions within 72 hours, the forecasters said.

Barry Baxter, a hurricane centre meteorologist, said forecasters had nudged the storm's track slightly to the west overnight but still had it narrowly missing a direct full-on hit to the U.S. coast.

It's still staying off the coast at this point for the whole eastern U.S., Baxter said.

He declined to predict how close the hurricane would come to New York when it churned offshore east of the city during the weekend.

It's too early at this point, Baxter said. We're just telling everybody to keep their eyes on the track and just keep checking back.

Forecasters expected Earl to stop just short of becoming a maximum Category 5 storm on the five-step Saffir-Simpson intensity scale.

Nevertheless, forecasters say Earl would bring drenching rain, dangerous seas and surf and gusting wind to the Atlantic Coast from North Carolina to New England and Atlantic Canada.

Earl, with top sustained winds of 135 miles per hour (215 kph), was moving away from Puerto Rico and the Virgin Islands on Tuesday and would cross the open Atlantic east of the Turks and Caicos Islands, the forecasters said.

At 11 a.m. (4 p.m. British time), it was centred about 205 miles (335 km) east of Grand Turk Island in the Turks and Caicos, a British territory at the southern tip of the Bahamas. That was about 1,070 miles (1,725 km) south-southeast of Cape Hatteras, North Carolina.

Tropical storm warnings and watches were in effect for the Turks and Caicos and the southeastern Bahamas.

Hurricane Earl posed no threat to major U.S. oil and gas installations in the Gulf of Mexico.

PUERTO RICO MOSTLY SPARED

Earl battered the northeastern Caribbean islands and Puerto Rico on Monday, downing power lines, blowing off roofs, toppling trees and causing some flooding. There were no immediate reports of casualties.

We have been quite fortunate. We did not take a direct hit ... it was not as serious as it could have been, Puerto Rico Governor Luis Fortuno told CNN.

Tropical Storm Fiona followed in Earl's wake on a similar path.

At 11 a.m. EST (4 p.m. British time), Fiona was 440 miles (705 km) east of the Caribbean Leeward Islands on a course that was expected to take it northeast of those islands on Wednesday. Most forecast models kept Fiona far away from the Gulf of Mexico.

With sustained winds of 40 mph (65 kph), Fiona was just barely a tropical storm and the much more powerful Earl was hindering Fiona's development. Earl churned up the seas and brought cold water to the surface, starving Fiona of the warm water needed for rapid strengthening.

The storms were 900 miles (1,440 km) apart but Fiona was moving much faster on a path that roughly traced Earl's. If Fiona closes the gap to about 300 miles (480 km), high-level winds spiralling from the top of Earl could shear off and weaken Fiona, the hurricane centre's Baxter said.

If it gets really close, Earl could actually chew it up and just kind of kill it, he said.

Elsewhere in the Atlantic, a broad area of low pressure about 400 miles (640 km) southwest of the Cape Verde Islands in the eastern Atlantic had only a 10 percent chance of becoming a tropical cyclone within 48 hours, the hurricane centre said.

Early computer models showed that system moving mostly west in the Atlantic but towards South America, not the energy-rich Gulf of Mexico.

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