Cyclonic storm over the East Siberian Sea
In meteorology, a cyclone is an area of low atmospheric pressure characterized by inward spiraling winds that rotate counter clockwise in the northern hemisphere and clockwise in the southern hemisphere of the Earth. The generic term covers a wide variety of low pressure areas.
The largest of the systems are cold core polar cyclones and extratropical cyclones which lie on the synoptic scale. Warm core cyclones such as tropical cyclones, mesocyclones, and polar lows lie within the smaller mesoscale. Subtropical cyclones are of intermediate size.