Severe Weather Science
Thunderstorms, hurricanes, and tornadoes
Remember…
_____________ is ALWAYS trying to equalize out, dangerous events
happen in the process of __________ trying to find balance in the universe!
Storms
* Definition:___________________________________________________.
* Formation: When a _______ pressure system moves into and around a
____ pressure system.
* Characteristics: formation of __________ __________ (cumulonimbus)
and mild/strong winds.
Types of Storms
* Ice storms
* blizzards
* _______ storm
*______________storm
* hurricanes
*tropical cyclones
*tornadoes
Thunderstorms
*Formation:
_____________________________________________________________
_____________________________________________________________.
* Characteristics: storm clouds (cumulonimbus), ____________, lightning,
strong winds, _______________.
~microbursts = strong wind gusts, last < 3 seconds
~ updrafts and _____drafts
* start forming in ____________ ______________ and move to middle
latitudes where they meet a _____, ____ front.
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Microbursts and Their Effects
* A powerful ______draft of wind that happens only for a few seconds,
usually invisible.
* Downdraft comes out of _________ clouds.
* Discovered due to air plane crashes that were taking off during _________.
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Science of Lightning
* __________________ clouds have positive and negative charges in them.
~negative charges are at the ___________ of the cloud.
~positive charges are at the ____________ of the cloud.
*Opposite attraction between cloud and ground.
*Cloud sends out “feeler of stepped leader” of __________ charge.
*Ground sends out a “positive streamer”
*Meeting in the _________“feeler-streamer”
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Fun Facts about Lightning
*A lightning charge contains about ____ million volts at 100,000 amperes.
*The total energy in a large thunderstorm is more than an_______________.
*About ____ U.S. residents are killed by lightning every year.
*The Empire State Building in NYC is struck by lightning about ____ times
every year.
*Air around a lightning bolt is heated to 54,000 degrees F (_____ times
hotter than the sun)
*Lightning bolt is usually less than ______ in diameter.
Hurricane Formation
*_______ and _______________ off the water of the oceans create a low
pressure region.
*_________________ systems move toward the low pressure area creating
heavy winds.
~Winds flow _____________ towards the center and up the eye
Characteristics of Hurricanes
*600 miles wide
* winds range from ___ to ____ mph
*move at 10-20 mph
*form over ____ degrees F water
*formation starts between 5-15 degrees latitude north/south of ___________
*season in northern hemisphere:
~Atlantic: June 1 to Nov 30
~Pacific: may 15 to Nov 30
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Hemispheres and Hurricanes
*Northern Hemisphere
*Southern Hemisphere
(counterclockwise)
(clockwise)
*Coriolis Effect
*Coriolis Effect
~path: ______________
~path: ______________
~rotation: ________________
~rotation:____________
NOTE: the _______ of a hurricane is _____________ the direction the
hemisphere is spinning, but the ______________ of any cyclone is
the______ as the rotation of the hemisphere that it is in.
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Formation of Tornadoes
* __________, _________ Fronts collide with ___________, __________
fronts.
* Upper horizontal wind rotation goes _____________.
*Column of vertically rotating air grows _____________ to the ground out
of a cumulonimbus cloud until it touches down to the ground.
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Picture 26 – Fujita Scale
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Weather Alert System
* __________________ are statements that tell us that conditions are
favorable for storms to form.
* __________________ are statements that describe storms and severe
weather that are happening.
*__________________/_______________ are statements describing
unusual or inconvenient weather conditions.