Meteorology. the variable frontal zone of middle latitudes separating air masses of polar and tropical origin.
Origin of polar front
First recorded in 1915–20
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meteorol a front dividing cold polar air from warmer temperate or tropical air
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The region or boundary separating air masses of polar origin from those of tropical or subtropical origin. The position of the polar front during winter in a particular hemisphere is at approximately 30° latitude, while in the summer it is at approximately 60° latitude. The convergence of warm and cool air masses along the polar front often produces cyclonic wind systems.
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