In a flash flood what does flash mean?

Question

In a flash flood what does flash mean?

Answer 1

Flash flooding happens very quick.  Flooding happens over a period of time.  If you get 3 inches of rain in 20 minutes, that is flash flooding, but if you get 20 inches of rain in 24 hours, that is just flooding.  During flash flooding, it happens very quickly, as in a flash, like the first guy said.  

Answer 2

Sudden, unexpected.  Happening "in a flash".

Answer 3

like unexpected flood just occured  

Answer 4

that its goning to happen quickly......if it was sudden or unexpected weather ppl couldnt tell us about them in advance

Answer 5

It primarily refers to rain falling in high volume over a short period of time which overwhelms the normal drainage ability of a particular area.  But any time a large volume of water enters an area at a rate that exceeds the drainage systems ability to handle it is a flash flood.  

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