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HURRICANES—Know the threat and be prepared.
Tangipahoa OHSEP hurricane information and checklists.
Hurricanes are products of the tropical ocean and atmosphere. Powered by heat from
the sea, they are steered by the easterly trade winds and the temperate westerlies as
well as by their own ferocious energy. Around their core, winds grow with great velocity,
generating violent seas. Moving ashore, they sweep the ocean inward while spawning
tornadoes and producing torrential rains and floods. In the Atlantic, Caribbean, and
Gulf of Mexico, hurricane development starts in June. For the US the peak hurricane
threat exists from mid-August to late October with the season officially ending
November 30th. Hurricane winds can exceed 155 mph and severely affect areas
hundred of miles inland. It is the wind and low pressure that create the storm surge.
A storm surge is a great dome of water often 50 miles wide,
that comes sweeping across the coastline near the area where the eye of the hurricane
makes landfall. The surge, aided by the hammering effect of breaking waves, acts
like a giant bulldozer sweeping everything in its path. The stronger the hurricane
and the shallower the offshore water, the higher the storm surge will be. If the
storm surge arrives at the same time as the high tide, the water height will be
even greater. This is unquestionably the most dangerous part of a hurricane.
Nine out of ten hurricane fatalities are caused by the storm surge. Hurricane
Camille in 1969 produced a 25 foot storm surge which
inundated Pass Christian, Mississippi.
Landfall is the term used to indicate the moment a hurricane
hits land. When a hurricane hits at a speed of 74 mph, the transaction of energy within
its circulation is great. The condensation heat energy released by a hurricane in one
day can be the equivalent of energy released by fusion of four hundred 20-megaton
hydrogen bombs.
Perception of Risk—Over the past several years, the warning
systems have provided adequate time for people on the barrier islands and coastline
communities to move inland when hurricanes threaten. However, it is becoming more
difficult to evacuate people from these areas because roads have not kept pace with
the rapid population growth. There are 45 million permanent residents along the
hurricane-prone coastline. In addition to these permanent residents, the holiday,
weekend, and vacation populations swell some coastal areas 10-100 fold.
The problem is further compounded by the fact that 80 to 90% of the population now
living in hurricane-prone areas have not ever experienced the core
of a "major hurricane." Many have been through weaker storms. The result is a
false impression of a hurricane's damage potential. This often leads to complacency
and delayed actions.
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A watch is when hurricane conditions are possible in the specified area
of the watch usually within 36 hours. Click HERE for a checklist.

A warning means that hurricane conditions are EXPECTED in the
specified area of the warning usually within 24 hours.
Click HERE for a checklist.

Shut off water, gas and electricity at the main source. Leave during daylight
hours if possible.

Tune to local news media, keep calm, stay indoors (even if the “eye” passes
directly in your path), shelter your family in the house opposite of the wind’s direction.

Stay indoors, avoid using the phone, don't attempt to drive anywhere, and don't weather the
storm in your boat or recreational vehicle.

Even though the storm has passed, there still may be life-threatening dangers
waiting outside. Click HERE for an Aftermath Checklist. |
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