Where Tide Clocks Work

Tide Timers are recommended for use on both Coasts of the United States and Canada.  On the Atlantic they never need adjustment.  On the Pacific, including Hawaii, they can be calibrated to different coastal locations using our proprietary setting tables but they must be set once a week on Saturdays to be accurate. See the NOAA chart below for many other areas around the world where tide clocks are effective.  Tide clocks will not work in the Gulf of Mexico.

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Basic Tidal Patterns

Tide clocks operate effectively when used in Semidiurnal tidal areas (red). Three basic tidal patterns occur along the Earth's major shorelines. In general, most areas have two high tides and two low tides each day. When the two highs and the two lows are about the same height, the pattern is called a semi-daily or semidiurnal tide. If the high and low tides differ in height, the pattern is called a mixed semidiurnal tide. Some areas, such as the Gulf of Mexico, have only one high and one low tide each day. This is called a diurnal tide. The U.S. West Coast tends to have mixed semidiurnal tides, whereas a semidiurnal pattern is more typical along the East Coast. Although the US and Canadian Pacific Coasts and Hawaii have mixed semidiurnal tides, our Tide Timers will operate effectively along the Pacific if they're used with Schelling Corporation's proprietary West Coast setting tables. (Sumich, J.L., 1996; Thurman, H.V., 1994; Ross, D.A., 1995).