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NOUS43 KILX 191452

952 AM CDT WED MAR 19 2014

The National Weather Service (NWS) has declared March 16th through
March 22nd as Flood Safety Awareness Week. The National Weather
Service in Lincoln will feature information about a different flood
topic each day during the awareness week.

Today`s Topic: Floods

Hazards: A flood is defined as any high flow, overflow, or inundation
of water that causes or threatens damage.  Flooding can occur with
prolonged rainfall over several days, intense rainfall over a short
period of time, or when water from an existing source moves too
quickly (i.e. snowmelt, dam break, etc.). Brief descriptions of the
various types of flooding you may experience are found below.  More
information about these flood hazards can be found on the NWS Flood
Safety Website at

Flash Flooding: Flash flooding is a rapid and extreme flow of high
water into a normally dry area, or a rapid water level rise in a
stream or creek above a predetermined flood level, beginning within
six hours of the causative event (i.e. intense rainfall, dam failure,
ice jam).

River Flooding: River flooding occurs when rivers rise and
overflow their banks, inundating areas that are normally dry.

Tropical Systems and Coastal Flooding: At any time of year, a storm
from over the ocean can bring heavy precipitation to the U.S. coasts.
Whether such a storm is tropical or not, prolonged periods of heavy
precipitation can cause freshwater flooding in coastal areas, as well
as further inland as the storm moves onshore. In addition to the
freshwater flood threat, tropical systems and nor`easters can bring
the threat of storm surge related coastal flooding.

Burn Scars/Debris Flows: Wildfires burn away the vegetation of an
area, leaving behind bare ground that tends to repel water. When rain
falls, it runs off a burn scar towards a low lying area, sometimes
carrying branches, soil and other debris along with it. Without
vegetation to hold the soil in place, flooding can produce mud and
debris flows.

Snowmelt: Flooding due to snowmelt most often occurs in
the spring when warming temperatures quickly melt the snow. The water
runs off the still partially frozen or already saturated ground into
nearby streams and rivers, causing them to rapidly rise and sometimes
overflow their banks.

Ice and Debris Jams: A backup of water into surrounding areas can
occur when a river or stream is blocked by a build-up of ice or other

Dry Wash: When heavy rain falls over dry land, the water
rushes towards low-lying areas, which may include dried up canyon or
stream beds. This can quickly turn a dry channel into a raging river.

Dam Break and Levee Failure: A break or failure can occur with little
to no warning. Most often they are caused by water overtopping the
structure, excessive seepage through the surrounding ground, or a
structural failure.

Understanding the different flood hazards and knowing the actions to
take before, during, and afterwards can help you protect your life,
the lives of your loved ones, and your property.  Prepare now by

Join us tomorrow for information on flood related services provided
by the National Weather Service.

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