Today is the second day of our Severe Weather Awareness Week for the Mid-South. We are going to focus on the topic of flash floods. Most of the information provided is by the National Weather Service and for more information you can visit http://www.srh.noaa.gov/jan/.
Flash Flooding
Flash floods can occur within a few minutes or up to 6 hours after excessive rainfall, a dam or levee failure, or a sudden release of water held by an ice jam or mud slide. Flash floods can wash out roads, destroy buildings and bridges. Due to flash floods occurring in a short period of time (less than six hours after the causative event) they are more life threatening than other types of flooding. Areas most susceptible to flash flooding are mountainous streams and rivers, urban areas, low-lying areas, storm drains, and culverts.
Warning
A Flash Flood Warning is issued when flash flooding has been reported or is imminent. It focuses on specific communities, creeks or streams, or other geographic areas where flooding is imminent or occurring.
River Flooding
This type of flooding is caused by an increased water level in established watercourses, such as a rivers, creeks, or streams. River flooding is slower to develop than flash flooding (more than 6 hours after the causative event), however, some smaller creeks and streams have a short lag time between the runoff from heavy rain and the onset of flooding. On the other hand, it may take several days for a flood crest to pass downstream points on major rivers such as the Lower Pearl, and Mississippi Rivers. The NWS issues River Flood Warnings when rivers are expected to rise above flood stage. Persons in the warned area are advised to take necessary precautions immediately. River stages and crest forecasts are given for selected forecast points along with known flood stages for each forecast point. While there is usually more advanced warning time with river floods than with flash floods, persons should be familiar with the flood prone areas they live and work in, and must know what action to take and where to go if a flood occurs. Advance planning and preparation is essential.
Flood Watch
The NWS issues a Flood Watch when conditions are anticipated that could result in either flooding or flash flooding within a designated area. Persons in the watch area are advised to check flood action plans, keep informed, and be ready to take action if a warning is issued or flooding is observed.
Flood Safety Rules
Follow these tips to stay safe during flood condition:
1. When a warning is issued get out of areas subject to flooding. If caught in low areas during flooding, go to high ground immediately.
2. Avoid already flooded and high velocity flow areas. A rapidly flowing stream or ditch can sweep you off your feet or even carry your car or truck downstream.
3. Never drive through a flooded area as the road bed may be washed away. Play it safe! If you encounter a flooded road... TURN AROUND, DON’T DROWN!
4. Be especially cautious at night when it is harder to recognize flood conditions, and never drive around a barricaded road. Most flood deaths occur at night and when people become trapped in automobiles that stall in areas that are flooded. If your vehicle stalls, abandon it immediately and seek higher ground. The rising water may engulf the vehicle and the occupants inside.
5. Do not camp or park your vehicle along streams or washes during threatening conditions.
When a FLOOD WARNING is issued for your area, act quickly to save yourself. You may only have seconds!
Here are a few videos: The first video is by NBC covering a flash flood story. The second video is by a guy who's screen name is TornadoChaser and he recorded a current flash flood. The last video is by a CNN ireporter covering a river/flash flood in Nashville, TN.
***Please be sure to pause the background music in order for you to really hear the audio from the video below. To do just that, scroll down to the very bottom of the page and you will be able to pause or stop the background music.***
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