Cyclone

Large scale rotating air mass

In meteorology, a cyclone is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. Cyclones have also been seen on planets other than the Earth, such as Mars, Jupiter, and Neptune.

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