The dome of water associated with a hurricane making landfall is called a storm surge. A storm surge is a rapid rise of the level of the sea above predicted tidal heights and it occurs because water is piled up against the coast by strong onshore winds as a result of the storm. Storm surges result in breaching of coastal defenses and widespread flooding. Storm surges lead to flooding along the coast and is a major hazard in the event of a hurricane; often the leading cause of death.