Occluded Fronts PowerPoint Presentation

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STANDARD GRADEOCCLUDED FRONTS
John Smith Invergordon Academy
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WHAT IS AN OCCLUDED FRONT?
You have already learned that the cold front
moves faster than the warm front.
The warm sector is squeezed upwards, so that is
right off the ground.
The result is an occluded front. It is what
happens when the cold front catches up with the
warm front.
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FORMATION OF AN OCCLUDED FRONT
Warm sector has been lifted off the ground
so has the warm front
W A R M F R O N T
OCCLUDED FRONT
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THE EFFECT OF AN OCCLUDED FRONT (1)
CIRRUS
CUMULUS
STRATUS
W A R M F R O N T
Dense cool air
LIGHT SHOWERS
PERSISTENT RAIN
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THE EFFECT OF AN OCCLUDED FRONT (2)
The approaching warm front looks normal cirrus
and then cumulus clouds, which bring rain.
The warm front does not reach the ground, it has
been replaced by a section of the cold front.
There are no warm southerly winds at ground
level. Instead, cold northerly winds are felt
behind the cold front.
The warm sector, now pushed high up, cools. This
is the end of the low pressure system, because
there is no more warm air rising away from the
Earths surface.