Transcript Severe weather - Cloudfront.net

Severe weather is any weather that is destructive.
The term is usually used to refer to:
•thunderstorms
•tornados
•tropical storms
•snowstorms/blizzards
• ice storms
•drought
•Small area storms formed by the strong upward
movement of warm, moist air
•Usually occur ahead of a cold front as the colder,
denser air shoves the warmer air upward
•This movement of air forms the cumulonimbus
clouds that produce thunderstorms
•These storms are accompanied by heavy rain,
thunder, lightning, sometimes hail, and can also
produce tornadoes
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All thunderstorms produce lightning
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Lightning is the discharge of huge amounts of
static electricity (think of walking across a
carpet in your socks and then touching
something-ZAP)
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Thunder is the result of the air quickly
expanding from the heat of the lightning bolt
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You cannot have lightning without thunder!!
Thunderstorm formations
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Form SEVERE storms and
tornadoes!
THIS IS ONE BIG STORM
SYSTEM!
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Form from very powerful thunderstorms
(cumulonimbus clouds)
These are funnel shaped columns of spiraling
winds that extend down to the ground from the
base of a cloud
The winds move into a tornado (low pressure), and
can reach a maximum of 318 mph!
Spin COUNTER CLOCKWISE (like a hurricane)
The actual funnel is made by water droplets
(clouds) and dust
HE WAS GOING TO TAKE A PICTURE OF THE LIGHTNING AND WAS UNAWARE OF
THE TORNADO UNTIL THE LIGHTNING ILLUMINATED IT.
This is a one-in-a-million photo..............
Taken Thursday night, April 3, 2008 . Lariat Sandridge Energy
South of Ft Stockton , TX
A blizzard is a severe winter condition
with low temperatures, strong winds,
and heavy blowing snow.
An ice storm is a type of winter storm
with freezing rain.
A drought is an extended period of months or years when a region
receives consistently little or no precipitation.
WILDFIRES are often the result of DROUGHT
A tropical storm is the overall name for a storm which is spinning.
They form when warm water heats the air causing it to rise really quickly, then it
gets pushed aside as it cools. This pushing causes the clouds to spin.
.
Different names for tropical storms:
•hurricane
•typhoon
•severe tropical cyclone
•tropical cyclone
Hurricanes are tropical storms
where the winds get faster than
118 km/h (73 mph).
The storms have a central area of
calm known as the "eye", which is
the funnel through which the
warm air rises.
Why are we seeing more of these
destructive storms?
El Niño is an abnormal warming of surface
ocean waters in the eastern tropical Pacific.
Strong winds blow from the east
along the equator, pushing warm
water into the Pacific Ocean
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The different water temperatures of these areas
effects the types of weather these two regions
experience.
 In the east the cool water cools the air above it, and the air
becomes too dense to rise to produce clouds and rain.
 In the western Pacific the air is heated by the water below
it, increasing the buoyancy of the lower atmosphere thus
increasing the likelihood of rain.
 This is why heavy rain storms are typical near Indonesia
while Peru is relatively dry.
An El Nino condition results from weakened
trade winds in the western Pacific Ocean
near Indonesia, allowing piled-up warm
water to flow toward South America.
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This flattens out the sea level, builds up warm
surface water off the coast of South America,
and increases the temperature of the water in
the eastern Pacific.
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What happens to the ocean also affects the
atmosphere.
Tropical thunderstorms are fueled by hot,
humid air over the oceans.
 The hotter the air, the stronger and bigger the
thunderstorms.
 As the Pacific's warmest water spreads eastward,
the biggest thunderstorms move with it.
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The clouds and rainstorms associated with
warm ocean waters also shift toward the east.
 So, rains which normally would fall over the
tropical rain forests of Indonesia start falling over
the deserts of Peru, causing forest fires and
drought in the western Pacific and flooding in
South America.
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The Earth's atmosphere responds to the heating of
El Niño by producing patterns of high and low
pressure which can have a profound impact on
weather far away from the equatorial Pacific.
 For instance, higher temperatures in western Canada and
the upper plains of the United States, colder temperatures
in the southern United States. The east coast of southern
Africa often experiences drought during El Nino.
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http://kids.earth.nasa.gov/archive/nino/
http://www.foxtoledo.com/files/2009/07/elnino.jpg
http://www.gma.org/surfing/weather/elnino.
html