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Diurnal tide Semidiurnal tide



Mixed semidiurnal tide

Diurnal tide cycle (upper left). An area has a diurnal tidal cycle if it experiences one high and one low tide every lunar day. Many areas in the Gulf of Mexico experience these types of tides.

Semidiurnal tide cycle (upper right). An area has a semidiurnal tidal cycle if it experiences two high and two low tides of approximately equal size every lunar day. Many areas on the eastern coast of North America experience these tidal cycles.

Mixed Semidiurnal tide cycle (lower middle). An area has a mixed semidiurnal tidal cycle if it experiences two high and two low tides of different size every lunar day. Many areas on the western coast of North America experience these tidal cycles.