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Here We Go Again?
NOAA's 2005 outlook sees another above-normal
season.
The National Oceanic and Atmospheric
Administration’s (NOAA) hurricane forecasters in May predicted another
above-normal hurricane season on the heels of last year’s destructive
and historic hurricane season (see HP, Fall 2004, page 16).
“NOAA's prediction for the 2005 Atlantic hurricane season is for
12 to 15 tropical storms, with seven to nine becoming hurricanes, of which
three to five could become major hurricanes,” said retired Navy Vice
Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans
and atmosphere and NOAA administrator. “Forecaster confidence that
this will be an active hurricane season is very high.”
NOAA's Atlantic hurricane outlook reflects an expected continuation of
above-average activity that began in 1995. Since that time all but two
Atlantic hurricane seasons have been above normal. Hurricane season started
June 1 and ends November 30.
“Impacts from hurricanes, tropical storms and their remnants do not
stop at the coast,” states retired Brig. Gen. David L. Johnson, director
of the NOAA National Weather Service. “As we . . . look at another
highly active season, preparation plans should consider that these storms
carry severe weather, such as tornadoes and flooding, while moving inland.”
PLANNING AND PREPARATION
Although it’s too soon to predict where and when a storm may hit
land, NOAA still cautions the public to be prepared.
“Last year’s hurricane season provided a reminder that planning
and preparation for a hurricane do make a difference. Residents in hurricane-vulnerable
areas who had a plan, and took individual responsibility for acting on
those plans, fared far better than those who did not,” said Max Mayfield,
director of the NOAA National Hurricane Center (see HP, Winter 2003, page
10).
The next update to the Atlantic hurricane outlook will be issued in early
August just prior to the season’s historical peak from late August
through October.
In contrast to the Atlantic, a below-normal hurricane season is expected
in the Eastern and Central Pacific. NOAA’s outlook for the Eastern
Pacific hurricane season calls for 11 to 15 tropical storms, with six
to eight becoming hurricanes, of which two to four may become major hurricanes.
Two or three tropical cyclones are projected for the Central Pacific.
The 2005 Atlantic hurricane outlook is a joint product of scientists at
the NOAA Climate Prediction Center, Hurricane Research Division and National
Hurricane Center. NOAA meteorologists use a suite of sophisticated numerical
models and high-tech tools to forecast tropical storms and hurricanes.
Scientists rely on information gathered by NOAA and the U.S. Air Force
Reserve personnel who fly directly into the storms in hurricane-hunter
aircraft; NOAA, NASA and the U.S. Department of Defense satellites; NOAA
data buoys, weather radars and partners among the international meteorological
services.
NOAA, an agency of the U.S. Dept. of Commerce, is dedicated to enhancing
economic security and national safety through the prediction and research
of weather and climate-related events and providing environmental stewardship
of the nation's coastal and marine resources.
Many of the hazards posed
by hurricanes are obvious, but there are related dangers to be aware
of.
STORM SURGE
Storm surge is simply water that is pushed toward the shore by the
force of the winds swirling around the storm. This advancing surge
combines with the normal tides to create the hurricane storm tide,
which can increase the mean water level 15 feet or more.
In addition, wind-driven waves are superimposed on the storm tide.
This rise in water level can cause severe flooding in coastal areas,
particularly when the storm tide coincides with the normal high tides.
Because much of the United States’ densely populated Atlantic
and Gulf Coast coastlines lie less than 10 feet above mean sea level,
the danger from storm tides is tremendous.
HIGH WINDS
The intensity of a landfalling hurricane is expressed in terms of
categories that relate wind speeds and potential damage. According
to the Saffir-Simpson Hurricane Scale, a Category 1 hurricane has
lighter winds compared to storms in higher categories.
A Category 4 hurricane would have winds between 131 and 155 mph and,
on the average, would usually be expected to cause 100 times the damage
of the Category 1 storm. Depending on circumstances, less intense
storms may still be strong enough to produce damage, particularly
in areas that have not prepared in advance.
Tropical storm-force winds are strong enough to be dangerous to those
caught in them. For this reason, emergency managers plan on having
their evacuations complete and their personnel sheltered before the
onset of tropical storm-force winds, not hurricane-force winds.
Hurricane-force winds can easily destroy poorly constructed buildings
and mobile homes. Debris such as signs, roofing material and small
items left outside become flying missiles in hurricanes. Extensive
damage to trees, towers, water and underground utility lines (from
uprooted trees) and fallen poles cause considerable disruption.
FLOODING
When it comes to hurricanes, wind speeds do not tell the whole story.
Hurricanes produce storm surges, tornadoes and often the most deadly
of all: inland flooding.
While storm surge is always a potential threat, more people have died
from inland flooding in the last 30 years. Intense rainfall is not
directly related to the wind speed of tropical cyclones. In fact,
some of the greatest rainfall amounts occur from weaker storms that
drift slowly or stall over an area.
Inland flooding can be a major threat to communities hundreds of miles
from the coast as intense rain falls from these huge tropical air
masses. |
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