Transcript Clouds, storms and the Bible

Severe Weather
Storms
Thunderstorms
Tornadoes
Hurricanes
What are Thunderstorms?
 Thunderstorms
are severe storms
from cumulonimbus clouds.
 Tornadoes grow from
thunderstorms.
 Lightening is a result of electric
sparks from storms. It gives off
noise – thunder.
Lightning and thunder happen at the same
time.
We see lightning before thunder
because light travels faster
than sound.
Stages of a Thunderstorm –
STAGE 1
 Air rises quickly due
to intense heating –
Updraft
 More and more
warm, moist air rises
making the cloud
grow bigger and
bigger.
 When updrafts can’t
keep water in, it falls
as heavy rain or hail.
STAGE 2
 As the rain falls, it causes air to
move downward – downdraft.
 As the air goes up it rubs
against the air going down,
static electricity builds up
creating sparks or lightening.
 Lightening jumps all around;
cloud to ground, ground to
cloud, between two
thunderclouds, different spots on
one cloud.
 Lightening slams around
creating thunder.
STAGE 3
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When the downdraft
becomes stronger
than the updraft,
heavy rain lightens
up and stops.
Thunderstorms
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Thunderstorms are more likely
when it has been hot and humid
and a cold front is approaching.
Thunderstorm Outdoor Safety Tips
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Go to a safe place immediately (a sturdy
building or car)
Stay away from trees.
If there’s no shelter, crouch down in an
open area.
Stay out of water. Don’t stand in puddles.
Avoid metal objects.
Wait at least 30 minutes after the last
observed lightning strike or thunder before
going back outside.
How and Where Do Tornadoes Happen?
 THE MOST VIOLENT STORMS!
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It is a violent, whirling wind that moves across the
ground in a narrow path.
When an updraft in a convection cell is VERY
strong, the air rushes in from all sides at varying
speeds.
Form where dry, cold air masses MIX with warm,
moist air masses.
The air curves and spins. Air rushes in fast,
lowering the pressure.
It gets faster and faster.
Tornadoes
In the center of the tornado,
winds can be up to 300 miles per
hour!!
 Their direction can change at any
moment.
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Where they Occur
In the Midwest and the south are the
most commonly seen.
 Great Plains, Mississippi Valley &
Florida
 Most often in early spring and the
summer.
 Waterspouts are tornadoes that form
over water.
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Tornado Safety Tips
Go to a basement.
 If you don’t have a basement, go to an
interior room on the lowest floor (ex. a
bathroom or closet)
 Get under sturdy furniture
 Stay away from windows.
 If outside, go to a ditch or low lying area
and lie flat.
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How Do Hurricanes Form?
Hurricanes are very large,
swirling storms with very
low pressure in the center.
What does that mean for
the high pressure outside?
 They form over tropical
oceans – near the equator.
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Formation of Hurricanes
A large, low-pressure center forms over the
ocean because of a lot of heating and
evaporating here.
 Then, winds blow IN toward the LOW
pressure. As it rushes in and upward, a tall
ring of thunderstorms form.
 Because of the Coriolis Effect, the winds
spiral counterclockwise.
 Thunderstorms are pulled into the spiral.
They ALL merge into ONE, LARGE storm.
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Formation of Hurricanes
As the water vapor in the air condenses, heat
is released.
 As a result, air density and pressure is
lowered.
 Low air pressure favors evaporation.
 The lower the air pressure, the faster the
winds that are blowing toward the center.
 When the winds reach about 75 miles per
hour or higher, we have a hurricane.
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Formation of Hurricanes cont’d.
As the moist air in the storm rises and cools,
condensation takes place.
 As a result, clouds thicken and heavy rain
falls.
 When fully formed, a hurricane has an eye at
the center.
 The eye is an area of light winds and skies
that are nearly clear.
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How Do Hurricanes Affect
Ocean Waves?
 As hurricanes move north away from the equator,
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their speeds increases.
Hurricanes create large waves in the oceans.
The waves pound on the shore even BEFORE the
hurricanes arrive.
The storm surge, great rise of the sea along the
shore, causes the most destruction.
When the pressure of a hurricane drops, the
surface of the sea rises forming a bulge beneath the
hurricane.
How Do Hurricanes Affect
Ocean Waves cont’d.
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When hurricanes move over a coast, the
bulge can cause water levels to rise
several feet (surge).
 During a great storm, the surge, large
waves, high winds, and torrential rain of
the storm happen at the SAME time.
 In effect, low-lying coastal areas become
flooded.
 Hurricanes die out when they move over
land because they have no water from the
ocean.
What Can You Do to Be Safe
in a Hurricane?
 Have
a disaster plan ready and
prepare an emergency supply kit.
 Board up windows and bring in things
from outdoors that might blow away.
 Be prepared to evacuate when
necessary.
 Listen to weather storm advisories.
How Can Radar Track
Storms?
Storms are harder to predict because of how
quickly they form.
 Doppler Radar is used to find storms as they
form.
 Radar works by sending out radio waves and
recording their echo.
 Differences in the echo at different times help
predict weather patterns and how often or
frequent those echoes are occurring.
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