By: Nick, Johnny, Tyler, Carly, Andrea

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Hurricanes, Typhoons and Tropical Cyclones
By Nick, Johnny, Tyler, Carly, Andrea
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Hurricanes, Typhoons and Tropical Cyclones
How They Form
There are several things that must be together
for a hurricane, typhoon or tropical cyclone to
form 1) Hurricanes only form over really warm
ocean water of 26.5 C or more. Ocean water in
the Maritimes never reaches this temperature so
hurricanes cannot form in these waters. 2) The
atmosphere must cool off very quickly the higher
you go. It is like when it gets really cold when
you reach the top of a mountain. 3) The wind must
be blowing in the same direction and at the same
speed from the ocean surface right up to 9,000
metres above sea level. 4) A hurricane will not
form any closer than 500 kilometres to the
equator. The Coriolis Force is needed to create
the spin in the hurricane and it becomes too weak
near the equator.
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Hurricanes, Typhoons and Tropical Cyclones
What Time of Year
Hurricanes, typhoons and tropical cyclones only
form in certain times of the year. The hurricanes
that impact eastern North America usually occur
between June and November every year. Most of
those hurricanes form and develop between August
and October. There is an old saying that on the
Labour Day weekend there will be a hurricane or
tropical storm somewhere in the North Atlantic.
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Hurricanes, Typhoons and Tropical Cyclones
Where is it More Common?
Hurricanes can only develop over really warm
ocean water. So no hurricanes are formed near
Canada. Well, hurricanes form over warmer water
but they can move around. Hurricanes can last for
days or even weeks and move huge distances. The
hurricanes and tropical storms that affect North
America usually form in the eastern Atlantic
Ocean where the water is very warm.
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Hurricanes, Typhoons and Tropical Cyclones
Recent Occurences
The most recent examples/occurrences
are 1. Tropical Storm Allison 2. Tropical Storm
Barry 3. Tropical Storm Chantal 4. Tropical Storm
Dean 5. Tropical Storm Lorenzo 6. Hurricane
Erin 7. Hurricane Felix 8. Hurricane
Gabriella 9. Hurricane Iris 10. Hurricane
Juliette 11. Hurricane Michelle 12. Hurricane
Noel 13. Hurricane Olga
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Hurricanes, Typhoons and Tropical Cyclones
Potential Distruction
Hurricanes are one of the most destructive of all
extreme weather events. In the last century
there has been Atlantic hurricane every year.
However, Atlantic hurricanes that make it to land
are not very numerous each year. But when they do
make it to land, it can be devastating. One
reason for such devastation is that unlike a
tornado which can span about a mile on the
ground, the hurricane and its effects can reach
hundreds of miles and last much longer. This way,
it affects many more people.
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Hurricanes, Typhoons and Tropical Cyclones
Factors of Weather
Ocean ImpactsThe high winds of a hurricane can
create very high waves on the open ocean. Also,
near the eye of the hurricane, the wind is going
in all directions. This is much more dangerous
than the wind of a winter storm that usually
blows only in one direction. These waves and high
winds are a hazard for shipping and boating.
Storm SurgeStorm Surge is the fast rise in sea
level that occurs as a big storm like a hurricane
approaches the coastline. The sea level near the
coast piles up because of the strong winds that
are pushing the water towards the coast and also
because of the storms low pressure that creates
a suction on the ocean, causing it to rise up.
WindsThe strong winds of hurricanes and
tropical storms can cause a lot of damage. Winds
can destroy houses, buildings, and other
structures. In major hurricanes, flying debris
can be very dangerous.
TornadoesSometimes hurricanes can create the
conditions necessary for tornadoes. These
tornadoes are usually pretty small but there can
be a lot of them. Hurricane Bertha of 1969
produced a swarm of tornadoes on the Texas coast.
This usually isnt a problem for Canada.
RainfallHurricanes can produce very heavy
rainfall. Sometimes days after a hurricane passes
there is extremely heavy rain. The heavy rains of
hurricanes and tropical storms can cause heavy
flooding.
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Hurricanes, Typhoons and Tropical Cyclones
DID YOU KNOW?
...that the largest Tropical Cyclone ever
recorded was 1110 kilometres across! ...that
the longest lasting Tropical Cyclone latest 31
days. This was Hurricane John in 1994. ...that
most tropical cyclones that near Canada are in
the process of dying? When the storms enter our
colder waters, they lose their main source of
energy. ...that only two category 3 hurricanes
have made landfall in Canada in the last 110
years. ...that only 3 or 4 tropical cyclones
affect Canada every year? ...that the deadliest
hurricane in Canadian history was in September
1775, when 4,000 people died along the south
coast of Newfoundland.