President Barack Obama has declared a state of emergency for six Pennsylvania counties in the wake of Wednesday's severe winter storm, including Lancaster and York counties.
The president's order also includes five southeastern Pennsylvania counties; Bucks, Chester, Delaware, Montgomery and Philadelphia.
The order clears the way for federal aid to assist state and local authorities with their emergency response efforts.
The Department of Homeland Security and the Federal Emergency Management Agency will coordinate the disaster relief efforts.
The snow and ice storm knocked out power to an estimated 849,000 Pennsylvania residents. More than half of those remained without electricity on Thursday, and officials have said it could take until Saturday before everyone has their service returned.
Governor Tom Corbett has said FEMA's assistance will be used to supply generators for hospitals and nursing homes.