India, Sept. 26 -- A powerful nor'easter is expected to batter the U.S. Northeast through the weekend. Forecasters have warned that Boston, New York City and the Jersey Shore will experience varying degrees of heavy rain, strong winds and coastal flooding.

The storm intensified Friday as it moved toward New England. Storm-force winds over the Atlantic produced massive waves along the East Coast. The National Weather Service (NWS) warned that dangerous conditions could persist into Saturday before the system begins weakening later in the day.

Forecasters said tens of millions of people are in the storm's path. Officials have already cancelled events, advised residents on islands near Cape Cod to travel to the mainland and issued evacuati...