The National Weather Service has issued a hurricane warning for Philadelphia as at the city lies almost directly in the path of Hurricane Irene.
The weather service issued the warning early Friday as the massive storm bears down on the East Coast.
The storm is expected to bring a half-foot of rain or more to the region along with damaging winds. Mayor Michael Nutter is advising residents of flood-prone areas to prepare for possible evacuation orders.
Forecasters say Irene will move into the area on Saturday with the strongest winds likely late that night and into Sunday afternoon.
Neighboring Delaware County is also under a hurricane warning with a tropical storm warning in effect in other counties west of the city.