Transcript Predicting Weather

Predicting Weather
Chapter 6 Lesson 3
Pages 304-310
Predicting Weather
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Look at the picture on page 304. What
do you notice? What do you wonder?
What are highs and lows?
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Scientists study how
air moves to predict
weather
Different types of
weather develop
around areas of high
and low pressure
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High pressure air is cool
and dry=dry, clear
weather
Low pressure air is
warm and humid=warm
and stormy weather
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When the barometer
reading drops
suddenly=precipitation
will fall
What are weather fronts?
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The weather in an area
is affected by the air
mass that is passing
over that area
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A large region of the
atmosphere in which the
air has similar properties
throughout
Several air masses can
be over a country at
any given time
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Air masses that form
over water tend to be
humid
Air masses that form
over land tend to be dry
Air masses that form in
the tropics are hot
Air masses that form in
the poles are cold
What are weather fronts?
A cold front occurs
when cold air moves
in under a warm air
mass
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Cold fronts bring
brief, heavy storms.
Air is usually cooler
and drier afterward
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A warm front occurs
when warm air
moves in over a cold
air mass
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Warm fronts bring
light, steady rain or
snow. Weather is
usually warmer and
more humid
afterward
What moves air masses?
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After an air mass
forms, global winds
may move it
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A jet stream is a
high-altitude wind
caused by large
temperature
differences between
air masses
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Over North
America, the jet
stream blows from
west to east.
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Fronts help you
predict future
weather.
Today’s weather is
typically yesterday’s
weather farther west
Answer=A Winds in
North America move
from west to east.
Whatever weather is
occurring on the
western part of the
country will eventually
make its way to the
east because the wind
will move it there!
What do weather maps tell
us?
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Weather maps show the
weather in a specific
area at a specific time
Meteorologists are
scientist who study
earth’s atmosphere and
weather
They track variables to
make forecasts, or
predictions about what
weather will occur
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Weather predictions are
NOT ALWAYS accurate
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Meteorologists will use
tools to make the best
prediction, but they will
not always be 100%.
Weather is
unpredictable because
we cannot control
nature!
What does weather look like?
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Heavy storms
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Dark clouds, heavy
precipitation
Long period without rain,
many crops can die
Sunny
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funnels forming in the sky,
high wind speeds
Drought
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Monsoon
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Tornado
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Skies are clear, temperatures
are warmer
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Hurricanes
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Heavy rain fall for a long
period of time (usually
weeks-months)
Precipitation is ANY FORM
OF WATER THAT FALLS
FROM THE SKY (rain, snow,
sleet, hail)
Swirling winds, dark clouds,
occurs over water!
Blizzards
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Heavy snow fall, dark skies,
usually in the winter in
areas further North