Hurricane Irene Track. A strengthening Hurricane Irene churned on a northwest track toward the Southeast United States Tuesday, threatening the Turks and Caicos Islands and the Bahamas with battering winds and rain and dangerous surf. While the U.S. National Hurricane Center's five-day forecast now sees a possible landfall in North Carolina this weekend, forecasters have been cautioning that such projections can have a margin of error of as much as 250 miles.

Irene, now a Category 2 storm, was heading over the Turks and Caicos and southeastern Bahamas. It was expected to become a major Category 3 storm, with winds over 111 mph, by Wednesday and intensify further to a Category 4 as it neared the southeast U.S. coast by Friday.

"Irene is forecast to become a larger than average hurricane," the Miami-based hurricane center said.

The powerful storm, the first hurricane of the busy 2011 Atlantic season, looks set to be the first hurricane to hit the United States since Ike pounded the Texas coast in 2008.

Authorities along the U.S. Atlantic seaboard, from Miami to New York, were closely watching Irene's possible path, with at least some computer forecast models showing it might even sweep up near New York City early next week.

"Everybody living on the eastern coast of the U.S. should monitor Irene and review their hurricane preparations over the next few days," Dr. Rob Carver, a hurricane expert with private forecaster Weather Underground, wrote in a blog Tuesday.

The storm could be the catalyst the insurance industry has been seeking in its quest for across-the-board premium increases, in what already promises to be the costliest year in history for natural disasters around the globe.

At 8 a.m., Irene had top winds of 100 miles per hour and was 55 miles northeast of Puerto Plata, Dominican Republic, and 70 miles south-southeast of Grand Turk Island.

The center of the hurricane was heading to the Turks and Caicos Islands and the southeastern Bahamas. The NHC warned "an extremely dangerous" storm surge would raise water levels by as much as 9 to 13 feet on the low-lying islands.

President Barack Obama, who was briefed about Irene while on vacation at the Massachusetts island of Martha's Vineyard, signed an emergency declaration Monday for Puerto Rico after the storm pummeled the U.S. island territory with heavy rains and winds.

Puerto Rican authorities reported power outages and some flooding, but there were no reports of deaths or injuries.

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