A strong storm system drops a deluge of rain over parts of the U.S. Northeast Thursday, flooding an area around Philadelphia.<br/> <br />Several Philadelphia residents had to be rescued by boat, after flood waters surrounded their apartment buildings.<br/> <br />Southern Pennsylvania, along with central New Jersey and Delaware, remain under a flood watch.<br/> <br />It's the latest round of severe weather following the worst floods in decades in Florida's Panhandle.
