Mid-Latitude Cyclonic Storms

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Mid-Latitude Cyclonic Storms

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• http//www.geog.ouc.bc.ca/physgeog/contents/7s.htm
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This is because the air masses have different
temperature and moisture characteristics. They
are, therefore, of different densities. Like oil
and water, they dont mix easily.
Mid-latitude cyclonic storms develop along the
boundaries of different air masses.
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To get precipitation to occur, air must rise and
cool to the point where condensation occurs. How
does the air rise in a mid latitude cyclonic
storm? At the cold front, cold air lifts warm air
aloft as the cold front moves into the warm air
sector. And warm air rises above the denser cold
air at the warm front.
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The following slides trace the development of a
theoretical mid-latitude cyclonic storm. The view
is from above.
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Air starts to rise as it beings to circulate
around the center of the storm.
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The storm dissipates or disappears eventually.
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What does a mid-latitude cyclonic storm look like
from the side or in cross-section?
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B
A
Note the line A to B
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Cross-section of a mid-latitude cyclonic storm
Because the air is being forced to rise,
mid-latitude storms are also called low pressure
cells or systems.
Precipitation
Condensation
Cold Front
Warm Air
Air cools
Cold Air
Air rises
Warm Front
Cold Air
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Warm front produced as warm air glides up over a
cold air mass. Precipitation is moderate and
occurs within a few hundred kilometers of the
surface front.
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Fast-moving cold front and cumulonimbus clouds.
Often thunderstorms occur if the warm air is
unstable.
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Stages in the formation of an occluded front.
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Distribution of clouds associated with an
idealized middle-latitude cyclone.