설명Norwegian cyclone model 2 wave forms on front, 3D view.jpg
English: A wave develops on the front as an upper level low pressure system, embedded in the jet stream moves, over the front. The front develops a "kink" where the wave is developing. The stationary front changes into a cold front and warm front as the air masses begin to move. Precipitation will begin to develop with the heaviest occurrence along the front.
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