FORT LAUDERDALE, Fla. One of the most powerful Atlantic Ocean hurricanes on record is barreling through the Caribbean and poses a serious threat to the southeastern United States, less than two weeks after Hurricane Harvey first hit Texas.

Irma weakened to a Category 4 hurricane early Friday after pummeling the Turks and Caicos islands overnight, but remained a life-threatening situation, the National Hurricane Center said .

The powerful storm has killed at least 19 people and left thousands displaced. It is expected to make landfall in southern Florida on Sunday, though the region will begin to feel hurricane conditions on Saturday, according to the NHC.

Meanwhile, two other storms Jose and Katia were upgraded to hurricane status on Wednesday afternoon, marking the first time since 2010 that three hurricanes were simultaneously spinning in the Atlantic basin.

Residents of the Caribbean islands where Irma has already wrought destruction are just beginning to pick up the pieces and assess the death toll as Jose, which was upgraded to a Category 4 hurricane Friday morning, approaches the easternmost islands of the Lesser Antilles.

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