Cyclone Arun

Cyclone From Wikipedia, the free encyclopedia Jump to: navigation , search This article is about the meteoro logi cal pheno menon. For other uses, see Cyclone (disambiguation) . Polar low over the Barents Sea on February 27, 1987 In meteorology , a cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth. [1][2] This is usually characterized by inward spiraling winds that rotate counter clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere of the Earth. Most large-scale cyclonic circulations are centered on areas of low atmospheric pressure. [3][4] The largest low-pressure systems are cold-core polar cyclones and extratropical cyclones which lie on the synoptic scale. Warm-core c ycl ones such a s tropical cyclones, mesocyclones , and polar lows lie within the smaller mesoscale . Subtropical cyclones are of intermediate size. [5][6] Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base o f the Tropical Upper Tropospheric Trough during the summer months in the Northern Hemisphere. Cyclones have also been seen on other planets outside of the Earth, such as Mars and Neptune. [7][8] Cyclogenesis describes the process o f cyclone formation and intensification. [9] Extratropical cyclones form as waves in large regions of enhanced mi dlatitude temperature contrasts ca lled baroclinic zones . These zones contract to form weather fronts as the cyclonic circulation closes and intensifies. Later in their life cycle, cyc lones occlude as cold core systems. A cyclone's track is guided over the course of its 2 to 6 day life cycle by the steering flow of the cancer or subtropical jet stream. Weather fronts separate two masses of air of different densities and are associated with the most prominent meteorological phenomena . Air masses separated by a front may differ in temperature or humidity . Strong cold fronts typically feature narrow bands of thunderstorms and severe weather , and may on occasion be preceded by squall lines or dry lines. They form west of the

Cyclone Arun

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