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STANDARD GRADE OCCLUDED FRONTS. John Smith Invergordon Academy. 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.
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STANDARD GRADEOCCLUDED FRONTS John Smith Invergordon Academy
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.
FORMATION OF AN OCCLUDED FRONT CUMULONIMBUS C O L D F R O N T The Cold Sector (cold, dense air) HEAVY SHOWERS Warm sector has been lifted off the ground… …so has the warm front W A R M F R O N T OCCLUDEDFRONT
THE EFFECT OF AN OCCLUDED FRONT (1) CUMULONIMBUS C O L D F R O N T The Cold Sector (cold, dense air) HEAVY SHOWERS CIRRUS CUMULUS STRATUS W A R M F R O N T Dense cool air LIGHT SHOWERS PERSISTENT RAIN
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 The warm front does not reach the ground, it has been replaced by a section of the cold front.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 Earth’s surface.