State College, Pennsylvania

... Pennsylvania severe weather awareness week...

Today is day four of Pennsylvania severe weather awareness week.

This week is also National flood safety awareness week.

This week we will cover various topics relating to severe weather
and weather safety.

Weather permitting... we will conduct a test Severe Thunderstorm
Warning for the entire state today. The test warnings will be
aired on NOAA Weather Radio... starting at 9 am for the western
counties. The central counties will have their tests start at 10
am. Finally... the eastern counties will have test warnings issued
at 11 am.

Our topic for today is river flooding and river flood safety.

Pennsylvania has an extensive river system that is Scenic and
beautiful. However... on occasion... these rivers can become
destructive... and even deadly. Significant... widespread river
floods have occurred in Pennsylvania in 1936... 1972... 1996...
2004... 2006... and during late January of this year.

What causes river floods?
Generally... prolonged periods of heavy rainfall... sometimes
combined with extensive snow melt... over a large part of the
commonwealth will cause the rivers to swell and occasionally flood.
This is especially true in late winter and Spring when the snowpack
of the previous winter melts. If the snow melts quickly and is
combined with heavy rainfall... major flooding could result such as
the floods that occurred in January 1996. The floods of 1996 were
the worst since the remnants of hurricane Agnes passed through the
state in June of 1972.

Our rivers can flood anytime of the year. In Summer... slow moving
thunderstorms can cause the rivers to flood. In late Summer and
fall... heavy rain from tropical storms and hurricanes are the
biggest cause of river flooding. During 2005... two land-falling
tropical cyclones - Katrina and Tammy - caused flooding over large
parts of the state.

River flooding can result in widespread property damage and may
result in loss of life. More than 50 percent of the deaths
associated with flooding are automobile related.

What does a Flood Watch mean?
A Flood Watch means there is potential for flooding to occur... not
that river flooding is occurring. The watch is typically issued for
many counties at a time... and is ideally issued 12 to 24 hours before
flooding is expected. This way... you will have enough time to prepare.

What you should do when a Flood Watch is issued?
Go about your normal activities... but make periodic checks of NOAA
Weather Radio or other media outlets for updates and possible flood
warnings. Get ready to move your personal property out of the areas
that are known to flood.

If you live or work in an area which is prone to flooding... have a
safe evacuation Route to use if flooding occurs. Make sure everyone
in your home or office knows where to go if flooding occurs.
Have a battery operated radio... and several working flashlights
available. Take precautions to secure your property.

What does a river Flood Warning mean?
A river Flood Warning means that river levels will exceed flood
stage at certain points along our larger rivers... like the
Susquehanna and Juniata rivers. River floods take longer to
develop than flash flooding... so they may not pose as much threat
to life... but can take a much larger toll on property.

What you should do when a river Flood Warning is issued?
If you live in the flood plain... be prepared to evacuate if
ordered to do so. Make sure you have all necessary items in the
event that you cannot return home for several days. Make
arrangements to protect your property by moving your valuables to
higher ground... or an upper level of your home. Listen for river
level forecasts that predict flooding. Obey evacuation orders from
emergency management or local law enforcement officials... avoiding
any roads that are or may be covered with water.

For additional information on flash floods and severe weather
check out our web site at:
weather.Gov/statecollege... all in lower case.

Our weather safety topic for Friday will be...
Skywarn severe weather spotters.

Now is the time to prepare for this year's severe weather season.