may 27- June 2, 2012 is... .
*****national hurricane preparedness week*****
*****hurricane and flooding preparedness week in virginia*****
*****hurricane awareness week in north carolina*****
tropical storm/hurricane names for the 2012 season
Alberto Beryl Chris Debby
Ernesto Florence Gordon Helene
Isaac Joyce Kirk Leslie
Michael Nadine Oscar Patty
Rafael Sandy Tony Valerie
William
Hurricane season extends from June 1 until November 30. In the mid-
Atlantic region... 80 percent of hurricanes that affect this area occur
between early August and mid October. Below you will find information
on hurricane impacts to coastal communities.
Today's topic - coastal hurricane impacts
The coastal devastation caused by a landfalling hurricane is well
documented. In general, the devastation is the result of wind... rain
and/or storm surge.
Wind - the effects of winds exceeding hurricane force are no secret.
And... the damage caused by winds higher than 100 mph can be mind
boggling. In fact... the damage is comparable to that from a weak to
moderate strength tornado (ef1 to strong ef2), although it's much
more widespread. Houses and other buildings can be severely damaged
or destroyed... and trees and power lines can be downed over large
areas. Although the damage caused by winds from a hurricane can be
significant, a larger threat to life can result from the hurricane's
storm surge.
Storm surge - storm surge is defined at the abnormal rise in water
level resulting from the wind and pressure forces associated with
a hurricane. The magnitude of the storm surge is a function of the
strength of a hurricane... it's track relative to the coastline... the
hurricane's forward speed... and the profile of the near-shore ocean
bottom. The highest storm surges associated with a hurricane are
in the right forward quadrant as you are moving with the storm. In
this quadrant... the combination of hurricane winds, large pressure
falls and storm motion creates a build-up of water that crashes
onshore as the hurricane makes landfall.
Higher surges occur when a hurricane makes landfall perpendicular
to the coastline. In addition... storm surge can be magnified when
the coast has a wide Continental shelf... or is dotted with bays or
"angled topography" (which funnel the water into narrow areas). The
highest storm surge in the Hampton Roads area since 1900 was
6.5 to 7 feet with the 1933 hurricane. This may seem significant.
However... records dating back to the 1600s and 1700s suggest that
storm surges as high as 15 feet (comparable to a category 3 or 4
hurricane) have impacted the Hampton Roads region. Only the
imagination can guess what impact a storm surge of this magnitude
would now have on coastal Virginia!!
In 2003... Hurricane Isabel caused unprecedented storm surge up
Virginia's mainstem rivers. As much as 9 feet of surge occurred in
the James River as far upstream as Richmond in association with
Isabel. Storm surge values in the 5 to 8 foot range were common up
the York... Rappahannock and Potomac rivers. In addition... waves of
5 to 10 feet on top of the storm surge caused considerable damage to
communities residing along these rivers. In 2006... the much weakened
remnants of Tropical Storm Ernesto combined with a large high
pressure area over New England to produce storm surge in parts of
Virginia that rivaled what was experienced during Isabel in 2003.
The worst storm surges ever to impact the U.S. Coast were associated
with the landfall of Hurricane Ike in 2008... Hurricane Katrina in 2005
and hurricane Camille in 1969. These storms caused storm surges of 20
feet or more in portions of coastal Mississippi /Katrina and
Camille/... and the Upper Texas coast /Ike/. More than 100 people died
from the storm surge associated with Camille... while the storm surge
from Katrina took even more lives. A storm surge of similar magnitude
accompanied the Galveston, TX hurricane of 1900, which killed more
than 6000 people... the largest hurricane death toll in U.S. History.
Rain - rainfall amounts during hurricanes frequently exceed 10
inches. However... coastal sections are generally immune to the
devastating flash floods which can inundate inland communities from
this magnitude of rainfall. Unfortunately, rainfall amounts this high
only worsen the amount of storm surge flooding of streets...
underpasses and low lying areas during a hurricane.
Tornadoes - tornadoes frequently accompany landfalling hurricanes...
mainly in the right forward quadrant as you move with the storm.
In 2004... nearly 70 tornadoes were spawned by tropical systems
affecting the commonwealth. 40 of these tornadoes occurred on
September 17th, 2004 as the remnants of Hurricane Ivan moved north
through Virginia. This is the largest single day tornado outbreak
ever in Virginia... and surpassed the record single year tornado
total. Hurricane Bertha, which made landfall on the North Carolina
coast in July of 1996, produced 6 tornadoes in Virginia. The wind
damage associated with intense hurricanes, like Andrew and Hugo... is
often so severe that determining whether or not tornadoes caused
some of the damage is difficult... if not impossible.
*******************************************************
The National Weather Service in Wakefield will issue public
information statements through Saturday covering various topics
related to hurricanes and hurricane preparedness in Virginia.
The Virginia department of emergency management, the North Carolina
division of emergency management, the amercian Red Cross, the
Virginia Department of Transportation and the National Weather
Service appreciate any help that you can give US to raise public
awareness about The Hazards that hurricanes pose to residents of
the mid-Atlantic region, and what they can do now to be prepared.
Additional information on the 2012 hurricane awareness Campaign,
hurricane preparedness tips, and hurricanes in general, is available
on the internet from several sources:
1). Virginia dept. Of emergency management home page:
http://www.Vaemergency.Gov/readyvirginia/stayinformed/hurricanes
2). North Carolina division of emergency management:
http://www.Ncem.Org/
3). Maryland emergency management agency:
http://www.Mema.State.MD.US/
4). National Weather Service Wakefield VA home page:
http://weather.Gov/akq
5). National Weather Service Sterling VA home page:
http://weather.Gov/lwx
6). National Weather Service Blacksburg VA home page:
http://weather.Gov/rnk
7). National Hurricane Center hurricane preparedness home page:
http://www.Hurricanes.Gov/prepare - contains new videos
and podcasts!!!
8). Federal emergency management agency home page:
http://www.Fema.Gov/hazard/hurricane/index.Shtm
9). American Red Cross home page:
http://www.Redcross.Org/
10). Virginia department of transportation:
http://www.Virginiadot.Org/travel/hurricane_default.Asp
Bill sammler
warning coordination meteorologist
National Weather Service Wakefield, VA
90 °F
68 °F
