Transcript Air Masses and Fronts

Air Masses and Fronts
SWBAT explain the ways that air masses and
fronts form; discuss the causes of severe
weather; explain how technology is used to
monitor and predict weather
Air Masses
 Air mass
– a large body of air that develops over a
particular region of Earth’s surface.
 Front
– a boundary where air masses of different
temperatures meet
Fronts
 Cold Front
– A cold air mass advances and pushes under a
warm air mass, forcing to rise.
– Can produce bands of violent storms
Fronts
 Warm Fronts
– Warm air advances into a region of cold air, and
slides up over the colder air
– Creates wide areas of precipitation
Fronts
 Stationary Front
– A warm and cold air mass meet, but neither
advances
– Can remain in the same location for days
– Cloudiness and precipitation occur along the
front
Fronts
 Occluded Fronts
– A fast-moving cold front overtakes a slower
warm front and pushes it up, running into
another cold front
– Can produce cloudy weather and precipitation
High and Low Pressure Centers
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Get your lab notebook
Title: Creating a Low-Pressure Center
Watch the demonstration
Answer questions 1 and 2, under analyze on
page 359
Severe Weather
 How do thunderstorms develop?
– They usually develop around cold fronts where
air is rapidly pushed upward
– Cumulonimbus clouds form causing water
droplets to fall into lower droplets and grow
large
– As the large droplets fall they cool the
surrounding air creating downdrafts and strong
winds
– Cumulonimbus clouds also create lightning and
thunder
Severe Weather
 Tornado
– a violent, whirling wind that moves in a narrow
path over land.
 Hurricane
– a large storm that begins as an area of low
pressure over tropical oceans.
With a partner
 Answer question 1-5 on page 362
 Be sure to answer in complete sentences.
 Finish for homework.