Q: What is a tropical cyclone?
|
A: A tropical cyclone is a warm core system that is vertically stacked and derives its energy from warm ocean waters. These cyclones go through several different stages as they transfer heat from the tropics to the poles.
Back To Top
|
Q: What are the stages that a tropical cyclone goes through?
|
A: There are four different stages that a tropical cyclone goes through before maturing into a hurricane. They are: 1.) tropical disturbance, 2.) tropical depression, 3.) tropical storm, and 4.) a hurricane.
Back To Top
|
Q: What is a tropical disturbance?
|
A: A tropical disturbance is a cluster of showers and thunderstorms with little or no circulation. Also
known as a tropical wave.
Back To Top
|
Q: What is a tropical depression? |
A: A tropical depression is a tropical disturbance that is a bit more organized, has a closed circulation, and wind speeds of 20 to 34 kts, or 25 to 38 mph.
Back To Top
|
Q: What is a tropical storm?
|
A: A tropical storm develops when a tropical depression gains wind speeds of 35 to 64 kts or 39 to 73 mph.
Back To Top
|
Q: What is a hurricane?
|
A: A tropical cyclone becomes a hurricane when its wind speeds reach or go above 65 kts, or 74 mph. After that, the hurricane is classified according to sustained winds and pressure by the Saffir-Simpson Scale.
Back To Top
|
Q: What is the Saffir-Simpson Scale?
|
|
A: The Saffir-Simpson Scale is scale derived by a meteorologist and a structural engineer that is used to determine the strength and severity of a hurricane.
Back To Top
|
Q: How many categories of hurricanes are classified in the Saffir-Simpson Scale?
|
A: Hurricanes are broken down into five different categories according to their power and potential damage they can do, which is determined by sustained wind speed and pressure.
Back To Top
|
Q: What is the eye of a hurricane?
|
|
A: The eye of a hurricane is small area of clear weather that denotes the center of lowest pressure in the hurricane. This is denoted by calm winds and even sunny skies.
Back To Top
|
Q: What is the eyewall?
|
|
A: The eyewall is the ring and heavy showers and thunderstorms that precede the eye of a hurricane. This is where the most severe weather, and highest sustained winds are usually reported.
Back To Top
|
Q: What is the Central Dense Overcast?
|
|
A: The Central Dense Overcast is the circular mass of clouds that rotate around the center, or eye of a hurricane. This portion is usually symmetric in nature.
Back To Top
|
Q: What are the outer bands of a hurricane?
|
|
A: The outer bands are a term given to the showers and thunderstorms that are along the periphery of a hurricane.
Back To Top
|
Q: What are the feeder bands of a hurricane?
|
|
A: The feeder bands are a term given to the showers and thunderstorms that follow the outer bands and precede the eyewall of a hurricane.
Back To Top
|
Q: What is the storm surge?
|
|
A: The storm surge is a term for the large dome of water that accompanies the landfall of a hurricane. It is responsible for approximately 90% of all deaths that occur in hurricanes.
Back To Top
|
Q: What is upwelling?
|
|
A: Upwelling is a term for colder water coming up from the ocean's surface while a hurricane is spinning about in the same area for a prolonged period of time. This usually caused the hurricane to weaken.
Back To Top
|
Q: What is wind shear?
|
|
A: Wind shear is a term given to upper level winds that blow from west to east against a westward bound hurricane, which tear up the hurricane's clouds, and hinders tropical development. .
Back To Top
|
Q: What is a Tropical Storm Watch?
|
|
A: A Tropical Storm Watch means potential danger as a tropical storm is about 48 hours away from landfall.
Back To Top
|
Q: What is a Tropical Storm Warning?
|
|
A: A Tropical Storm Warning means danger is developing as a tropical storm is about 24 hours away from landfall.
Back To Top
|
Q: What is a Hurricane Watch?
|
|
A: A Hurricane Watch means that possible danger is developing as a hurricane is about 36 to 48 hours away from landfall.
Back To Top
|
Q: What is a Hurricane Warning?
|
|
A: A Hurricane Warning means that a life threatening situation is imminent as a hurricane is less than 24 hours away from landfall.
Back To Top
|
Q: What are the effects associated with a hurricane?
|
|
A: The effects that are most commonly associated with a landfalling hurricane include: 1.) heavy rain, 2.) high winds, 3.) waves and storm surge, 4.) tornadoes, and 5.) flooding.
Back To Top
|
Q: What are the most common origins of such tropical cyclones as hurricanes?
|
|
A: The three most common origins of tropical storms and hurricanes are in the following regions: 1.) Gulf of Mexico, 2.) Western Caribbean, and 3.) Near the Cape Verde Islands off the coast of West Africa.
Back To Top
|
Q: What are the most common tracks of tropical storms and hurricanes?
|
|
A: The most common tracks of tropical storms and hurricanes are the following: 1.) Originating off the West Coast of Africa near the Cape Verde Islands, and traveling westward toward the Caribbean and the East Coast of the United States, 2.) Originating in the Western Caribbean, and moving into the Gulf Coast, or along the East Coast of the United States, and 3.) Originating In the Gulf of Mexico, and moving into the Gulf Coast states from Texas to Florida.
Back To Top
|
Q: Why are tropical storms and hurricanes named?
|
|
A: The reason why names are given to tropical storms and hurricanes is because naming them makes it easier for residents in the affected area to recognize, remember, and understand.
Back To Top
|
Q: How are tropical storms and hurricanes named?
|
|
A: Tropical storms and hurricanes are named by the National Hurricane Center by using a six year rotating list of male and female names. Whenever, there is a powerful hurricane such as Hurricane Andrew (1992), which makes landfall and causes death and damages, the name is then retired from the list to avoid future confusion.
Back To Top
|
Q: What is the National Hurricane Center?
|
|
A: The National Hurricane Center is part of the United States Department of Commerce. It's primary function is to provide advisories, warnings, and forecasts on tropical storms and hurricanes to residents along coastal areas of the United States.
Back To Top
|
Q: What are the average number of named storms each hurricane season?
|
|
A: The average number of tropical storms each season is between 9 and 10 named storms each hurricane season.
Back To Top
|
Q: What are the average number of hurricanes each hurricane season?
|
|
A: The average number of hurricanes each season is between 5 and 6 named storms each hurricane season.
Back To Top
|
Q: What are the average number of major hurricanes each hurricane season?
|
|
A: The average number of hurricanes each season is between 2 and 3 named storms each hurricane season.
Back To Top
|
Q: Can a tornado occur in a hurricane? Why or why not?
|
|
A: Yes, a tornado can occur in a hurricane because of the tremendous instability in the atmosphere caused by the friction between a landfalling hurricane, and the area its affecting, particularly in its Northeast quadrant where winds are the strongest, and the counterclockwise flow around it is prevalent. However, these tornadoes are usually minimal in strength, which is equivalent to F0 or F1 on the Fujita Scale.
Back To Top
|
Q: Are there any benefits to having a hurricane?
|
|
A: Believe it or not, yes. Hurricanes are play a very important role in preserving the heat balance that the earth maintains by transferring heat from the tropics to the poles. They also can be very helpful to areas affected by drought with their torrential rains.
Back To Top
|
Q: What was the deadliest hurricane to make landfall in the United States?
|
|
A: The deadliest hurricane to make landfall in the United States happens to be the worst natural disaster in American History. It was the Great Galveston Hurricane of 1900, which struck on September 8, 1900, and left some 6,000 to 8,000 people (maybe more) dead.
Back To Top
|
Q: What was the costliest hurricane to make landfall in the United States?
|
|
A: The costliest hurricane in United
States History was also the costliest natural disaster in United States
History. Hurricane Katrina replaced Hurricane Andrew by causing at least
some $81 billion dollars in damage along the Gulf Coast including Louisiana,
Mississippi, and Alabama. Costs could go much higher than that with
final estimates going as high as $200 billion dollars.
Back To Top
|
Q: What was the strongest hurricane to make landfall in the United States?
|
|
A: The strongest hurricane to ever make landfall in the United States was the Labor Day Hurricane of 1935, which roared through the Florida Keys. It had a central pressure of 26.35 in of Hg/892 mb of Hg when it made landfall over Key West, Florida.
Back To Top
|
Q: How many Category Five Hurricanes have made landfall in the United States?
|
|
A: Three: The Labor Day Hurricane
of 1935, Hurricane Camille, which struck the Mississippi Gulf Coast
in August, 1969 with 180 mph winds, and killed 250 people from Louisiana
to Virginia, and Hurricane Andrew, which struck South Florida in August,
1992.
Back To Top
|
Q: Who are the Hurricane Hunters?
|
|
A: They are a group of meteorologists
and air force pilots, which fly into and around hurricanes to research
and investigate them so that they can make a forecast on where they will
go, and how strong they will become.
Back To Top
|
Q: What is rapid intensification?
|
|
A: Rapid intensification is a process in
which a tropical storm, or a minimal hurricane rapidly deepens in a short
amount of time. Examples of such storms that underwent rapid intensification
are Hurricane Hugo in 1989, Hurricane Andrew in 1992, Hurricane Opal in 1995,
Hurricane Isabel in 2003, and Hurricane Charley in 2004.
Back To Top
|
Q: What is eyewall replacement?
|
|
A: It is a process that major hurricanes,
especially powerful major hurricanes undertake when they try to reorganize,
and get stronger. An outer eyewall develops around the original eyewall,
and begins to sap the inner eyewall of its intensity and moisture, and thus
become the dominant eyewall.
Back To Top
|
Q: What was the costliest tropical storm in
United States History?
|
|
A: Tropical Storm Allison. This storm formed
in the Gulf of Mexico during the first week of the 2001 Atlantic Hurricane
Season, and dumped over 30 inches of rain in the Houston, Texas area leaving
behind over $4 billion dollars in damage.
Back To Top
|
Q: What is the average duration of a hurricane
at Category Five strength?
|
|
A: Not very long. Usually, it is quite amazing
to see a hurricane last for more than 24 hours at Category Five Hurricane
intensity. However, there have been several powerful hurricanes that have
been able to reach such an intensity, and maintain it for over 30 hours.
These storms include Hurricane Isabel in September, 2003, and Hurricane Dog
in 1950.
Back To Top
|
Q: Why are powerful hurricanes usually small?
|
|
A: Very interesting question. Hurricanes
such as Andrew, the Labor Day Hurricane of 1935, and Hurricane Camille were
all powerful hurricanes at Category Five strength, but also quite small relative
to other storms. This was most likely because the storms were so powerful
with high winds, that in order to conserve momentum, their size was smaller
than hurricanes such as Gilbert or Hugo. Gilbert, which was a Category Five
Hurricane at one point, grew tremendously in size after moving over the Yucatan
Peninsula, and dropped significantly in intensity to 120 mph winds.
Back To Top
|
Q: What are concentric eyewalls?
|
|
A: Concentric eyewalls are a phenomena that
are a product of both rapid intensification and eyewall replacement, where
two eyewalls develop within a hurricane causing it to weaken. An example
of concentric eyewalls occurring was in Hurricane Gilbert as it moved through
the Yucatan Peninsula, and back out into the Gulf of Mexico in September,
1988.
Back To Top
|
Q: What was the fastest moving hurricane ever?
|
|
A: The Long Island Express of 1938. In a
period of six hours, this powerful and devastating Category Three Hurricane
rapidly moved northward from Cape Hatteras, North Carolina to New England
in about six hours. The storm moved as fast as 70 mph up the coast.
Back To Top
|
Q: Have there been any hurricanes in the South
Atlantic?
|
|
A: Yes, but they are very rare. Perhaps
a few every century. Water temperatures are much colder in this region due
to the presence of the Benguelan current, which emanates off of Southwest
Africa. An example of a hurricane in the South Atlantic was a hurricane that
struck the Catarina region of Southeastern Brazil in March, 2004.
Back To Top
|
Q: When has the greatest number of named storms
occurred?
|
|
A: Twice. In September 2003 and August 2004.
There were eight named storms that formed during both these months.
Back To Top
|
Q: What was the lowest pressure ever recorded
in an Atlantic Hurricane?
|
|
A: When Hurricane Wilma approached
the Yucatan Peninsula in October, 2005. Hurricane Hunter aircraft flew
into the storm on the evening of October 19th, and found a minimum central
pressure of 26.05 inches of Hg, or 882 millibars. It surpassed the mark
set by Hurricane Gilbert in September, 1988.
Back To Top
|
Q: What was the longest lasting hurricane in
the Atlantic?
|
|
A: Not Hurricane Alberto in August, 2000.
Even though Alberto lasted three weeks, and was the longest lasting storm
ever during the month of August. It was only the third longest lasting storm
on record behind Hurricane Ginger in 1971, and the San Ciricao Hurricane
of 1899 that impacted Puerto Rico, and lasted for 33 days before going through
the
Azores
as a
Category
One
Hurricane, and became extratropical shortly afterward.
Back To Top
|
Q: What was the most rainfall ever record in
an Atlantic Hurricane?
|
|
A: Hurricane Mitch in October, 1998. Over
a three to four day period, the Category Five Hurricane dumped approximately
75 inches of rain over the Central American country of Honduras. The deluge
devastated Honduras leaving at least 11,000 people dead.
Back To Top
|
Q: What were the most names used by the NHC
in an Atlantic Hurricane Season?
|
|
A: Twenty-eight in 2005. The 2005
season was the most active hurricane season ever with the National Hurricane
Center going through the entire list of storm names assigned for that
season, and for the first time ever, going through a secondary list
from the Greek alphabet. 1933 previously had the most storms with 21,
but the National Weather Service and the National Hurricane Center didn't
start using names until 1950.
Back To Top
|
Q: Are there such things as Arctic Hurricanes?
|
|
A: Hurricanes are warm core systems that
only flourish in the tropical or subtropical regions. With that said, there
are Mid-Latitude Cyclones, or Nor'easters that have winds at, or in excess
of hurricane force. Some of these can actually be remnants of former hurricanes
too.
Back To Top
|
Q: What influence does El Nino have on Atlantic
Hurricanes?
|
|
A: Fortunately for those along the Eastern
Seaboard of the United States from Texas to Maine, El Nino occurrences have
a negative impact on Atlantic Hurricanes. The warmer than normal sea surface
temperatures
created
in the Pacific influence global climate in such a way that it makes hostile
upper level wind conditions throughout the Atlantic Basin, which tend to
shear the vertically stacked hurricane structure apart. An example of an
El Nino year was in 1997 when there were only eight named storms.
Back To Top
|
Q: What influence does La Nina have on Atlantic
Hurricanes?
|
|
A: Unfortunately for residents along the
Eastern Seaboard from Texas to Maine, La Nina events usually mean active
hurricane seasons in the Atlantic. The cooler than normal sea surface temperatures
in the Pacific result in more favorable upper level wind conditions in the
Atlantic, which help hurricanes and tropical storms flourish. An example
of a La Nina year was 1995 when there were 19 named storms, 11 hurricanes,
and 5 major hurricanes.
Back To Top
|
Q: Why can't hurricanes form near or on the
equator?
|
|
A: Because there is no spin created there.
Storms in the Mid-Latitudes to the subtropical regions tend to have an angle,
which allows for a spin or rotation to develop. No such things exist near
or on the equator. There are rare storms such as Hurricane Ivan in September,
2004, which form in extremely low latitudes.
Back To Top
|
Q: Why do hurricanes travel westward?
|
|
A: Hurricanes travel in a westward direction
because in the tropics and subtropics, the Bermuda High, Bermuda-Azores High,
or the Subtropical ridge is the primary steering feature in the Atlantic.
Air rotates clockwise around a high pressure system, which creates an easterly,
or southeasterly flow that pushes tropical storms and hurricanes to the west.
Back To Top
|
Q: Do Hurricanes transport salt water with
their circulation?
|
|
A: Quite possible. Hurricanes have been
known to transport things such as birds from tropical lands to places such
as New England. The salt in the salt water probably travels with the storm,
and is probably used as condensation nuclei that the storm's precipitation
can form from. Remember, in order for rain to form, the moisture must be
able to stick on to something so that it can accumulate.
Back To Top
|
Q: Do Hurricanes or Tropical Storms change
their name when they move into a different basin?
|
|
A: Yes. If a hurricane or tropical storm
that starts out in one region, or basin moves into another, it changes its
name from the one it had in the initial basin to the current available name
on the list for the new basin. For example, in August, 2004, Tropical Storm
Earl developed in the Atlantic. Then, after dissipating into an open wave
in the Central Caribbean, Earl's remnants crossed into the Eastern Pacific
via Central America, and regenerated into a hurricane, and was named Frank.
Back To Top
|
Q: What year had the most named storms
in the Atlantic Basin?
|
|
A: 2005. The 2005 season broke a lot
of records, and this was one of them. It was the most active season
ever, and the second time in a decade that more than 18 named storms
in the 1995 season. Previous record was 21 during the 1933 season.
Back To Top
|
Q: What is the record for most hurricanes
in an Atlantic season?
|
|
A: 15. This was another mark set in
the record breaking season of 2005. The previous mark was 12 set in
the 1969 Atlantic Hurricane season.
Back To Top
|
Q: What is the record for the most major
hurricanes in a season?
|
|
A: Eight. This mark was set in 1950,
and stood tall after the hectic season of 2005, which tied for second
with seven. 1961 also had seven major hurricanes.
Back To Top
|
Q: What is the record for the most Category
Five Hurricanes in a season?
|
|
A: Four. This mark was set in 2005
as well. Katrina, Rita, Wilma, and after further evaluation, Emily all
attained the highest level a hurricane have on the Saffir-Simpson Scale.
Previous mark was two set in 1961.
Back To Top
|
Q: What is the statistical peak of the
Atlantic Hurricane Season?
|
|
A: September 10th. This is because
of the lag in time that exists between maximum land temperatures and
maximum sea temperatures. Remember, in order for a hurricane to form
and flourish, sea surface temperatures have to be at least 80 degrees
Fahrenheit.
Back To Top
|
Q: What is an extratropical storm?
|
|
A: An extratropical storm is one that
is a cold core system. Many times these storms, which can also be called
Mid-Latitude cyclones, can develop from a decaying tropical storm that
loses its tropical characteristics.
Back To Top
|
Q: What are the differences between an
extratropical and tropical system?
|
|
A: As mentioned before an extratropical
system is one that is also called an Mid-Atlantic cyclone. It is also
a cold core system meaning it has cold air in the area of lowest pressure.
In addition, extratropical storms are tilted systems which is because
low pressure at different levels are not stacked right on top of each
other until they fully mature. These systems also have wind shear with
wind blowing in opposite directions with height. These systems are often
described as baroclinic in nature. Meanwhile, tropical systems are warm
core systems that have warm air in the area of lowest pressure, vertically
stacked with the low pressures at the surface, mid, and upper levels
in sync, and they don't like wind shear. These systems are often described
as barotropic in nature.
Back To Top
|
