Flash Flood 

Flash floods are rapid and unexpected floods that occur suddenly, 6-12 hours or less after the corresponding heavy rainfall event. They occur after a short or no warning and they last for a very short time. They result from the sudden and rapid increase in water level, which is accompanied by high water speeds. They occur especially in hilly or mountainous areas with steep slopes. Disastrous flash-floods are much more frequent in some parts of the Mediterranean region (including Greece and Cyprus) than in the rest of Europe. Surface runoff resulting from flash floods is very important with respect to flood duration and it presents a serious threat to constructions and infrastructure. Due to the short time for warning, preparation and evacuation, the loss of human life may be a significant consequence of flash floods.