The White House says President Barack Obama is being briefed on Hurricane Irene during his vacation.
White House spokesman Josh Earnest says FEMA is in close contact with states and U.S. territories that have already been impacted by the storm or could be impacted as it moves toward the U.S. mainland.
Hurricane Irene cut power to more than a million people in Puerto Rico on Monday but there were no reports of deaths or major injuries. Forecasters are warning it could threaten Florida and South Carolina by the end of the week.
The president is vacationing on Martha's Vineyard, a wealthy island enclave off the Massachusetts coast.