Transcript Document

A Presentation on Hurricane Basics. Part of the Hurricane
Learning Series By Hurricaneville.
Hurricane Basics
1
7/18/2015
AGENDA
Introduction
Factors In Hurricane Development
Stages Of Hurricane Development
The Saffir-Simpson Scale
Components of a Hurricane
Origins of a Hurricane
Hurricane Tracks
Effects from a Hurricane
Naming of Hurricanes
Credits
Hurricane Basics
2
7/18/2015
Introduction
Hurricane Basics
3
7/18/2015
INTRODUCTION
Hurricanes are among the most fiercest forces on earth.
They are a vast mass of clouds that form in the tropics, and
bring heat to the poles.
These tropical cyclones bring high winds, heavy rains, and
dangerous tides from the coast to areas farther inland.
Hurricane Basics
4
7/18/2015
INTRODUCTION
Hurricanes occur throughout all the tropical regions of the
world.
Consequently, they are described with different terminology.
They are called Typhoons in the Western Pacific, Cyclones in
the Indian Ocean and Southern Pacific, and sometimes WillyWillys in Australia.
Hurricane Basics
5
7/18/2015
Factors In Hurricane Development
Hurricane Basics
6
7/18/2015
FACTORS IN HURRICANE
DEVELOPMENT
Hurricanes can develop into very powerful storms if the
conditions in the atmosphere are right.
Below are several key factors in hurricane development.
First, you need a spin—Tropical Disturbances develop from
the convergence of trade winds in the tropics. All tropical
systems must have some sort or rotation.
Warm water a must---Hurricanes are a vast heat engine that
need sea surface temperatures to be at least 80 degrees in
order to grow and mature.
No shearing allowed—Unlike tornadoes, hurricanes are a
vertically stacked system that move from east to west.
Therefore, they must have high pressure and light winds
aloft.
Hurricane Basics
7
7/18/2015
Stages Of Hurricane Development
Hurricane Basics
8
7/18/2015
STAGES OF HURRICANE
DEVELOPMENT
Hurricanes go through several different stages of
development before they reach hurricane status.
Tropical Wave--Is the first step toward a hurricane. They are
areas of low pressure that lack a closed center of circulation.
About hundred of these develop each year in the Atlantic
Ocean.
Tropical Depression--Develops when a tropical wave develops
a closed low level circulation, and wind speeds in excess of
20 knots, or 25 mph.
Tropical Storm—Develops when a tropical depression has
sustained wind speeds of 35 knots, or 39 mph.
Hurricane—Develops when a tropical storm has sustained
wind speeds of 65 knots, or 74 mph.
Hurricane Basics
9
7/18/2015
The Saffir-Simpson Scale
Hurricane Basics
10
7/18/2015
THE SAFFIR-SIMPSON
SCALE
Once a tropical system matures to a hurricane, it can
continue to strengthen to even greater heights.
The stronger the hurricane, the more catastrophic the
damage can be upon landfall.
Below is the Saffir-Simpson Scale, which is used to measure a
hurricane’s intensity and potential for damage.
Category
Winds
Pressure
Damage
One
74-95 mph
>=28.94 in.
Minimal
Two
96-110 mph
28.50-28.91 in.
Significant
Three
111-130 mph
27.91-28.47 in.
Severe
Four
131-155 mph
27.17-27.88 in.
Extreme
Five
>155 mph
<27.17 in.
Catastrophic
Hurricane Basics
11
7/18/2015
Components Of A Hurricane
Hurricane Basics
12
7/18/2015
COMPONENTS OF A
HURRICANE
There are several key components to a mature hurricane: The
Eye, Eyewall, Central Dense Overcast, and Outflow.
Below is a brief explanation of each.
The Eye—Is the center of circulation, and area of lowest
pressure in tropical storm or hurricane. It is most notably
known as the deceptive area of calm in the storm.
Eyewall—It is the solid ring of showers and thunderstorms
surrounding the eye. This is where the hurricane’s highest
winds are usually located.
Central Dense Overcast—The circular mass of embedded
showers and thunderstorms in the heart of a hurricane.
Outflow—Probably the most critical piece of a hurricane’s
machinery. It is the outer fringes of the hurricane where heat
energy is released into the atmosphere.
Hurricane Basics
13
7/18/2015
Origins Of A Hurricane
Hurricane Basics
14
7/18/2015
ORIGINS OF A
HURRICANE
Hurricanes form in several regions of the Tropical Atlantic.
Below is a brief description of each.
Gulf of Mexico—This region is the most conducive for
hurricane development throughout the year with sea surface
temperatures between 85 and 90 degrees.
Western Caribbean—This region is where a lot of hurricanes
form in the initial and final months of every hurricane
season.
Cape Verde Islands—This region is commonplace for the
development of the classic hurricane that occurs during the
peak months of August and September of each hurricane
season.
Hurricane Basics
15
7/18/2015
Hurricane Tracks
Hurricane Basics
16
7/18/2015
HURRICANE TRACKS
Hurricanes take several basic routes depending on there
origin.
Below is a brief description of each.
Forming in the Gulf of Mexico, and heading northward into
the Southeastern United States.
Forming in the Western Caribbean, and moving into Central
America, or the Yucatan Peninsula, and then later moving
into the Gulf before landfalling again in Northern Mexico, or
Southern Texas.
Forming near the Cape Verde Islands, and moving West
through the Caribbean, and then either making landfall
along the Gulf Coast, or Eastern Seaboard of the United
States.
Hurricane Basics
17
7/18/2015
Effects From A Hurricane
Hurricane Basics
18
7/18/2015
EFFECTS FROM A
HURRICANE
Hurricanes can bring a variety of effects. Some are greater
than the others.
Below is a brief description of each.
Rain—Probably the most underrated of all effects from a
tropical storm or hurricane. Amounts can be as high as
several feet.
Wind—The next most devastating effect behind storm surge,
hurricanes can have winds up to and above 200 mph.
Tornadoes—Many do not realize it, but hurricanes can
produce tornadoes upon landfall. The friction between the
storm and land produces a great deal of instability, and thus,
Tornadoes.
Storm Surge—The most deadly effect from a hurricane, this
rising dome of water that accompanies landfall accounts for
about 90 percent of all hurricane deaths.
Hurricane Basics
19
7/18/2015
Naming Of Hurricanes
Hurricane Basics
20
7/18/2015
NAMING OF
HURRICANES
Tropical Storms and Hurricanes are often referred to by name
throughout the world, particularly in the Atlantic Basin.
They are named so that it is easier to explain and effectively
communicate information on them to residents that could be
effected.
The National Weather Service began naming tropical storms
and hurricanes in 1953 by using names of girls.
In 1979, The National Hurricane Center got with the times,
and gave tropical storms, and hurricanes boys names as well.
The National Hurricane Center has a complete list of current
names of tropical storms and hurricanes for the current six
year cycle as well as a list of retired names.
Hurricane Basics
21
7/18/2015
Credits
Hurricane Basics
22
7/18/2015
CREDITS
Hurricaneville
Greg’s Weather Center
Hurricane City
The Weather Channel
The National Hurricane Center
Rutgers Meteorology Department
World Book Encyclopedia
Essentials of Meteorology: An Invitation To The
Atmosphere.
The Weather Book
Hurricane Basics
23
7/18/2015
We here at Hurricaneville hoped you enjoyed, and learned
a lot from this presentation.
Hurricane Basics
24
7/18/2015