By the time Hurricane Sandy exited the eastern coast of the United States in the early days of November 2012, it had killed 125 people in the U.S., shut down the nation's financial markets for the first time in more than a century, caused the majority of New York City to lose electricity, brought subways and commuter trains to a halt and, famously, stranded an iconic roller coaster in the sea, a stone's throw from its once-permanent location on a pier in Seaside Heights, N.J. [source: The Atlantic].
Sandy's record-setting storm surge was responsible for an estimated $62 billion in damage and loss in the U.S., as well as $315 million and 71 deaths in the Caribbean. It's no wonder this storm wreaked havoc; Sandy measured a 5.8 out of 6 on NOAA's storm scale [source: Associated Press].
But why did Sandy turn into such a superstorm in the first place? It seems a nor'easter may be partially to blame. Just as the hurricane headed northward along the coast, leaving Florida for the Eastern Seaboard, it seemed to head out into the Atlantic -- until a force pushed the warm air mass back toward land. That force? A cold nor'easter, whose powerful winds wrangled with the tropical hurricane, morphing it into a hybrid part nor'easter, part hurricane and making it capable of gale force winds, snow and rain [source: Gannett].