Hurricanes
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The cyclone season is upon us. In the North Atlantic, including the Caribbean Basin, it starts on 1 June and ends on 30 November; in the Northeastern Pacific, it starts on 15 May and finishes on 30 November. What can we learn from this meteorological phenomenon? Interesting and valuable information can be found to help us learn more about one of the most violent phenomena on planet Earth.

What Is A Hurricane?

A hurricane is a violent storm arising in the tropical oceans, approximately between 15° North and 5° South.

It is characterized by a significant low pressure center, surrounded by clouds organized in the shape of a spiral that, in the Northern hemisphere, turn counterclockwise.

A hurricane is defined by winds of more than 120 Km per hour, torrential rains, and strong tides. An essential element that contributes to this phenomenon is surface sea temperature, which must be equal to or higher than 27°C.

Hurricanes dissipate when they hit the coast or veer towards colder waters, where they cannot receive enough energy to remain active.

Where Does The Word “Hurricane” Come From?

“Hunrekan”, “Hurekan” or Hurakan” was the name given by the Mayans, Quiches and Tainos to the god of storms and diabolical spirits.

In other parts of the world, this meteorological phenomenon is known by other names:
India………. Cyclone
The Philippines ………. Baguio
Northwestern Pacific ………. Typhoon
Australia ………. Willy-Willy
Haiti ………. Taino


Regions Where Hurricanes Occur

North Atlantic: Caribbean, Gulf of Mexico, Western Atlantic
North Pacific: Western Mexico, Western Pacific, Sea of Japan, China Sea, the Philippines
India: Gulf of Bengal, Sea of Arabia
South Pacific; Northern Australia, Coral Sea
Western Indian Ocean: Madagascar, eastern coast of South Africa
Eastern Indian Ocean: Northeastern Australia, Sea of Arafura, Southern Indonesia

The Story Behind Hurricane Names

For many years, hurricanes were identified with the names of saints. (This went on from the 18th Century to the first half of the 20th.) After World War II, in the middle of the 20th Century, a code in alphabetical order began to be used to facilitate ease of transmission and the plotting of maps of these phenomena.

In 1953, the Meteorological Service of the United States decided to being using women’s names in alphabetical order. In 1978, it was decided to alternate between women’s and men’s names in the hurricanes that arise in the Northeastern Pacific. In 1979, alternate male and female names were incorporated into the lists of cyclones in the Atlantic and the Gulf of Mexico.

 

The specific names included in the list each year are selected in international meetings of the World Meteorological Organization (WMO). Member countries decide on the names.

The letters Q, U, X, Y and Z are not used to name the Atlantic ocean hurricanes, given the scarcity of names beginning with those initials.

When the impact of specific hurricanes is particularly devastating, causing a large number of deaths and considerable economic damage, the name is retired from the list, and may not be used for at least another 10 years.

Hurricane Warnings and Watches

The National Hurricane Center in the United States issues hurricane advisories and warnings. What do these terms mean?

Hurricane warning means that within the next 24 hours a particular area is expected to suffer from either or both of these dangerous effects of hurricanes: winds of 118 Km an hour or faster, or high waves even if winds are not quite as strong.

hurricane watch warns specific areas that a hurricane may hit them within the next 36 hours.

Did You Know?

Hurricanes can cause significant floods and tornadoes. Tornadoes take place in the storm areas along bands of rain that are somewhat removed from the heart of the hurricane.


Names Chosen For Tropical Cyclones In The Northeastern Pacific And The North Atlantic (Including The Caribbean And Gulf Of Mexico) For The 2001 Season

  • Pacific Ocean: Adolph, Barbara, Cosme, Dalila, Erick, Flossie, Gil, Henriette, Israel, Juliette, Kiko, Lorena, Manuel, Narda, Octave, Priscilla, Raymond, Sonia, Tico, Velma, Wallis, Xina, York, Zelda.
  • Atlantic Ocean: Allison, Barry, Chantal, Dean, Erin, Felix, Gabrielle, Humberto, Iris, Jerrye, Karen, Lorenzo, Michelle, Noel, Olga, Pablo, Rebekah, Sebastian, Tanya, Van, Wendy.

 

Hurricane Categories
Hurricanes are also classified according to the Saffir-Simpson Scale.
These are the categories:

Categorķa

Intensity of Sustained winds

1

84 a 96 Knots (153-178 km/h)

2

97 a 113 Knots (179-210km/h)

3

114 a 135 Knots (211-250km/h)

4

135 Knots or higher (+ 250km/h)

Prevention Measures Worth Sharing

Prepare a Family Home Evacuation Plan

  • Identify where you can go if you are advised to leave your home. Consider various places: a friend's home in another city, a hotel, a shelter.
  • Have at hand the phone numbers of those places, as well as a highway map of your locality. It may be necessary to take alternative routes, including unknown routes, if the main highways are closed or congested.


Make sure you have the following:

  • First-aid kit and essential drugs and medical supplies.
  • Tinned food and a tin opener.
  • At least three gallons of water per person.
  • Protective clothing, weatherproof garments and bedclothes or sleeping bags.
  • A battery-operated radio, a torch or flashlight and spare batteries.
  • Special items for babies, the elderly, or handicapped family members.


Prepare for strong winds.

  • Place storm blinds or pre-cut plywood ½? boards on each window of your home. Hammer supports for the plywood boards into the walls and drill holes into the supports to make it easier to hammer or screw the boards into place.
  • Help trees to resist the wind by cutting down damaged or weak branches. Remove other branches strategically to allow the wind to blow through them.

 

What To Do If A Hurricane Watch Is In Effect

  • A battery-operated radio, a torch or flashlight and spare batteries.
  • Listen to your local radio or TV stations for up-to-the-minute information on the storm.
  • Be prepared to bring indoors your garden furniture, decorations or exterior ornaments, garbage containers, hanging plants, etc.
  • Get ready to cover all the windows in your home. If storm windows have not been installed, use precut plywood boards as already noted. (Please note: Adhesive tape does not prevent window glass from breaking, so it is not advisable to use adhesive tape on windows.)
  • Fill up your car's gas tank.
  • Check to make sure you have spare batteries and store tinned food, first-aid equipment, drinking water and drugs in a place that is readily accessible.


What To Do If A Hurricane Warning Is In Effect

  • Pay attention to the announcements of local authorities and evacuate your home if you are so advised.
    If no evacuation orders are issued, remain within your home, far away from the windows.
  • Bear in mind that the eye of the storm can fool anyone: the storm is not over yet. In fact, the worst part of the storm will take place once the eye has passed over your home and winds are blowing in the opposite direction. The trees, shrubs, buildings and other objects damaged by the first set of winds may be additionally damaged or totally destroyed by secondary winds.
  • Pay attention to the likelihood of tornados. Tornados may occur not only during a hurricane but after it has passed. Remain indoors, near the center of your home, inside a closet or in a windowless bathroom.
  • Stay away from flooded areas. If you run into a flooded highway, turn around and try another route. If you are trapped in a flooded highway, leave the car immediately and head for higher ground.


What To Do After the Hurricane Is Over?

  • Continue to listen to local radio or TV stations in case additional instructions are issued.
  • If you had to leave your home, go back to it when local authorities confirm that it is safe to do so.
  • Check to see if your home suffered damages.

Jaquelina Michienzi
Senior Meteorologist-Expert on
Camera Meteorologist
The weather Channel LatinAmerica
Abril 2001