Tidal waves are formed by gravitational forces of the sun, moon and earth. The gravitational pull of the sun and moon tug on the ocean, causing waves to swell. As the earth completes its rotation, the tides move in and out. When the waves meet the shore, they are pushed back by the hard surface.
Tidal waves should not be confused with tsunamis. Tsunamis are powerful ocean waves caused by geological disturbances instead of gravitational pulls. Geological disturbances that cause tsunamis include earthquakes, landslides and volcanic eruptions.Learn more about Weather & Tides