Hurricane Sandy was an extremely large and destructive Category 3 Atlantic hurricane which ravaged the Caribbean and the coastal Mid-Atlantic region of the United States in late October 2012. It was the largest Atlantic hurricane on record as measured by diameter, with tropical-storm-force winds spanning 1,150 miles (1,850 km). The storm inflicted nearly $70 billion USD in damage, and killed 233 people in eight countries, from the Caribbean to Canada. The eighteenth named storm, tenth hurricane, and second major hurricane of the 2012 Atlantic hurricane season, Sandy was a Category 3 storm at its peak intensity when it made landfall in Cuba, though most of the damage it caused was after it became a Category 1-equivalent extratropical cyclone off the coast of the Northeastern United States.

An Atlantic hurricane is a type of tropical cyclone that forms in the Atlantic Ocean primarily between June and November. The terms "hurricane", "typhoon", and "cyclone" can be used interchangeably to describe this weather phenomenon. These storms are rotating, organized systems of clouds and thunderstorms that originate over tropical or subtropical waters and have closed low-level circulation, not to be confused with tornadoes. They form over low pressure systems. In the North Atlantic, central North Pacific, and eastern North Pacific, the term "hurricane" is mainly used, whereas "typhoon" is more commonly used for storms originating in the western North Pacific. The term "cyclone" is used in the South Pacific and Indian Ocean.