What are the signs of a tsunami coming?

Signs of an Approaching Tsunami

Natural indicators of a tsunami include intense or prolonged shaking from earthquakes, a loud noise resembling a train or airplane coming from the ocean, and odd behaviors observed in the sea. The water may appear to surge rapidly, resembling a flood or a massive wall of water. Alternatively, it might recede dramatically, exposing the ocean floor, reefs, and marine life much like an unusually low tide.