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...Flash Flooding...
Earlier today, we discussed an important flash flood safety program: Turn around don't drown. As part of Severe Weather Awareness Week, the National Weather Service wants you to be aware of the dangers of the number one storm killer: flash flooding. A flash flood is a rapid rise of water along a stream or in a low-lying urban area. Flash flooding can result from slow-moving thunderstorms, from numerous thunderstorms which develop repeatedly over the same area, and from heavy rains associated with tropical cyclones. These floods may develop within minutes, depending on the intensity of rainfall, the topography, soil conditions, and ground cover. Few people realize the true power of water. Rapidly-moving flood waters only six inches deep can knock an adult off their feet. Two feet of water can lift approximately 3000 pounds, which is the weight of an average-sized vehicle. Vehicles crossing a flooded roadway can lose traction with the road, actually floating in some cases. In some cases, water can erode the earth underneath a road, causing it to wash out. If a vehicle becomes overturned, it can fill with water, endangering the lives of its occupants. Flash flood statistics indicate that half of the annual flood fatalities are vehicle-related. Flash floods can roll boulders, tear down trees, destroy buildings and scour out new channels. Underpasses can fill rapidly with water. In urban areas, storm drains may become overwhelmed, allowing roads and buildings to flood. Low spots such as underground parking garages and basements can quickly flood. In rural areas, people who enjoy hunting, camping and fishing need to stay away from streams if strong thunderstorms have occurred. Water can rise over ten feet in less than an hour with a heavy rainfall. So how can we stay safe from the dangers associated with flash flooding? Monitor weather radio and pay close attention to flash flood warnings issued by the National Weather Service. Be especially cautious at night when it is more difficult to recognize the dangers of flash flooding. Avoid low lying areas that are prone to flooding. Don't camp or park your vehicle along streams and washes. If your vehicle is suddenly caught in rising water, leave it immediately and move to higher ground. Lastly, never attempt to cross areas where water covers the road. Remember the first safety rule of flash flooding...Turn around don't drown. Tomorrow, Severe Weather Awareness Week continues as we discuss the importance of amateur radio and storm spotters, and how to report severe weather to the National Weather Service.

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