This tsunami above is from Japan in 2011

Flooding can be caused in a number of ways, but one of the more extreme yet uncommon ways is from tsunamis. A tsunami is a series of waves caused by underwater volcanic explosions and earthquakes. These waves, however, are much bigger and more powerful than regular waves.

The waves tend to be between 10-100 feet tall, and travel between 20-30MPH. These waves often travel far inland, sometimes even more than a mile causing large amounts of damage.

Hawaii is always at great risk for a tsunami – they get about 1 per year and a severe one every 7 years. The biggest tsunami that occurred Hawaii happened in 1946, the coast of Hilo Island was hit with 30 ft waves at 500 mph.

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Most of the time the flooding will last between 5 minutes to two hours but sometimes the flooding can last for days.