Transcript What are Fronts?

What are Fronts?
An interface (boundary)
between 2 air masses
Conditions at the front are
unstable and usually
associated with
precipitation
Types of Fronts: Page 13 in R.T.
Cold Fronts:
Cold air
moves into
an area
occupied
by warm
air
The colder, denser air
quickly pushes under the
warm air
The warm air rises,
producing tall, thick clouds
Precipitation occurs –
moves quickly and
violently
Temperatures are cooler
behind a cold front, and
warmer ahead of the cold
front.
Cold Front Animation
Warm Fronts:
Warm air
mass
moves
into an
area
occupied
by cool air
The warmer, less dense
air slowly moves over
cold air mass
Warm air slowly rises,
expands, cools, and
clouds form
Lasts for a longer
period of time
Temperatures are warmer
behind a warm front, and
cooler ahead of the front.
Warm Front Animation
What is Severe Weather?
A tornado
warning is
issued …..how
do you
prepare?
A hurricane is a
few days
away…..how do
you prevent
damage from
occurring?
You live on the
coast….how do
you prepare for
a hurricane?
You live in
Kansas…how
do you
prepare for a
tornado?
Hurricanes
Hurricanes:
A low pressure system
with winds blowing
counterclockwise in
speeds in excess of 74
mph.
Hurricane season from
June 1 to November 30
Form at low
latitudes over warm,
tropical water (off
the coast of Africa)
Lose their energy as
they come onto land
Long island history
• The Long Island Express (1938): Cat 3
• The Great Atlantic Hurricane (1944):
Cat 4
• Carol (1954): Cat 3
• Donna (1960) Cat 3
• Gloria (1985) Cat 1
FYI!!!!!!
• Long Island is brushed every 6 years
• Long Island has a direct hit every 28
years
• Last one……Tropical Storm Charley in
2004
• Next predicted brush with fate……
• 2010
Hurricane Gloria 1985
1992 –
Hurricane
Andrew
KATRINA
The Eye of the storm:
The central
area of calm
weather
Violent winds
surround the
eye.
Hurricane winds and storm
surge (flooding) cause severe
damage to coastal areas
Storm Surge
Hurricane Damage
The Saffir-Simpson Scale
A scale (1-5) used to
classify hurricanes
Based on wind speed,
air pressure, storm
surge, and expected
damage
Category 1 Hurricane
Category 4 Hurricane
Tornado Alley
cP
mT
What are
Tornadoes?
Low pressure systems
that form when warm,
moist (mT) air collides
with cold, dry air (cP)
Produce funnel shaped
clouds
Winds blow
counterclockwise in
speeds from mph 40 -318
mph
Vortex – center of funnel
(very low pressure)
Destruction is sudden and
unpredictable
A funnel cloud lowers
towards the ground
The Funnel of a tornado
touched down on May 12, 1997,
in Miami, Florida
Not Smart…
Tornadoes that form over
water are called water spouts
Tornado path
Tornado Damage
Aerial View of
Tornado
Destruction
What are the differences
between hurricanes and
tornadoes?
Hurricanes are larger
than tornadoes
Hurricanes can be
watched and tracked for
days, whereas tornadoes
are extremely hard to
predict and only last for a
few minutes.
Hurricanes form
over water and lose
energy over land,
whereas tornadoes
form over land.
Tornado winds are
much faster
A tornado
warning is
issued …..how
do you
prepare?
A hurricane is a
few days
away…..how do
you prevent
damage from
occurring?
You live on the
coast….how do
you prepare for
a hurricane?
You live in
Kansas…how
do you
prepare for a
tornado?
What to do????
A hurricane is
coming...
Board up the
windows
Tie down any loose
outside objects
Stock up on nonperishable items
Evacuate to higher
ground
Hurricanes could
affect your area….
Stock up on bottled
water and non-perishable
items
Have batteries, candles
and flashlights
Have a generator handy
Have an evacuation route
prepared
Build house with
hurricane proof materials
Don’t live near the
water!!!!
And………..
A tornado warning is
issued…
Move to the center of
your house away
from windows
Move to a basement
or storm cellar
If in a field….crouch
down low in a ditch
You live in tornado
alley…..
Have non-perishable
food items ready
Have candles,
batteries and
flashlights
Build your house
with tornado
resistant materials
Have a storm cellar
installed