An incredibly dangerous day of severe thunderstorms including the potential for long-lasting, powerful tornadoes and hurricane-strength wind gusts is underway in the eastern half of the United States.

A potent cluster of thunderstorms that ripped down trees and flooded roads in parts of the region may have spawned a tornado in South Jersey on Friday afternoon. And the National Weather Service has issued another severe thunderstorm watch for for the entire region in effect until 11:59 p.