Severe Weather Preparedness Week 2013
Day 2 - Tuesday February 5, 2013
Today is day two of Severe Weather Preparedness Week. Our topic of
discussion today is flash flooding.
Flash flooding is a result of sudden, heavy rainfall commonly produced from
slow-moving intense thunderstorms or multiple rounds of thunderstorms
occurring over the same area. Flash floods become raging torrents of water
which rip through creek beds, city streets, and areas of poor drainage, sweeping
away everything before them.
Significant flash flooding has occurred across parts of the
southeastern states over the last few years. Some examples include
flash flooding near Atlanta in august 2009 and in Nashville in may
2010. In each of these cases the rainfall rates overwhelmed the drainage
systems and flooding beyond the experience of local residents occurred.
these floods resulted in numerous fatalities, a large portion of which
were elderly people.
In September 2011, the remnants of Tropical Storm Lee produced rainfall amounts
from 10 to 13 inches across Central Mississippi. This caused extensive flooding
of creeks and streams, but fortunately no loss of life. In August 2012, Hurricane Isaac
moved ashore very slowly causing tremendous flooding to portions of Southeast Mississippi
where storm total amounts were 10 to 15 inches. This flooded numerous structures and
some water rescues were performed in the Pine Belt region.
Most deaths from flash flooding occur when vehicle operators
drive their automobiles into flood waters of unknown depths only
to find the water is deeper than they thought. At this point, the
motor becomes inundated then stalls and the vehicle is soon swept
away, taking the passengers with it. A simple rule to remember is
Turn Around Don't Drown.
A flash flood watch means it is possible that heavy rains will
cause flash flooding in the specified area. Stay alert to the
weather, and think about what you would do if water begins to rise
or if you receive a warning. Watch for development of heavy rain.
A flash flood warning means flash flooding is occurring or
imminent in the specified area. Move to higher, safe ground
immediately!
A flash flood emergency means that extremely heavy rainfall has already
Occurred, will continue to occur, and that emergency officials are
reporting life-threatening rises in water that are resulting in water
rescues and or evacuations.
Below are some flash flood safety rules:
If you are driving, look ahead and watch for flooding at highway dips,
bridges, and low areas. Do not try to drive across water-filled areas
of unknown depth.
Be especially cautious at night when it is harder to recognize
flood dangers. Heavy rain events frequently and notoriously
occur at night.
Do not camp or park your vehicle along streams or drainage areas
particularly during threatening conditions. Avoid already flooded
and high velocity flow areas. Do not attempt to cross a flowing
stream on foot where water is above your ankles.