The circulation is counterclockwise in the Northern Hemisphere. The entire storm dominates the ocean surface and lower atmosphere over tens thousands of square miles. Hurricane winds also drive enormous surf before them, and help the storm tides with the work of flooding.
Storm tides are a hurricanes worst killer.
As the storm approaches and moves across he coastline, it brings huge surges, raising tidal sea levels 10 to 20 feet or more above normal. The rise may come rapidly and produce flash flooding of coastal lowlands, or may come in the form of giant waves. Hurricane storm tides do other types of damage. Flooding pollutes water supplies, cripples communications, shorts out power lines, causes sewers to back-up and overflow, undermines structures, and drastically revises shipping channels and shorelines. Torrential rains associated with hurricanes often cause widespread flooding, even after the storm has moved inland and has begun to die.