Occluded front

Occluded front symbol from a weather map

An occluded front is a weather pattern. It brings cold weather and leaves cold weather. It happens when a cold front overtakes a slow-moving warm front. The cold front is heavier than the warm front and will push it up. The warm front slides over the cold one. Cloud and rain form along the occluded front until temperatures become equal as the cold and warm air mix. Some occluded fronts make tropical cyclogenesis.

Occluded Front Media

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  Diagram of a cyclone in the early stages of occlusion in the Northern Hemisphere

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  Occlusion principle with positions of warm/cold occlusion fronts and the trowal