Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Floods ?
    ### Response:
    Floods are common in the United States. Weather such as heavy rain, thunderstorms, hurricanes, or tsunamis can cause flooding. Flooding can also happen when a river or stream overflows its bank, when a levee is breached, or when a dam breaks. Flash floods, which can develop quickly, often have a dangerous wall of roaring water.
    