Except
for fires, floods are the most common form of natural disaster.
They can be caused by frequent rain, heavy thunderstorms and
snow melt. In coastal areas, floods can occur when storms
blow onshore and pile ocean water against the coast. Hurricanes
can cause flooding over a large area. Floods can occur slowly,
such as when rivers rise because of too much rain, or quickly.
When floods occur without warning they are called flash floods.
Flash floods often happen in mountainous areas when a storm
up stream causes the water level downstream to rise quickly.
If you do not move to higher ground quickly you could be trapped.
