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A sting jet is a meteorological phenomenon which has been postulated to cause some of the most damaging winds in extratropical cyclones, developing according to the Shapiro-Keyser model of oceanic cyclones. ==Concept== Following reanalysis of the Great Storm of 1987, led by Professor Keith Browning at the University of Reading, researchers identified a mesoscale flow where the most damaging winds were shown to be emanating from the evaporating tip of the hooked cloud head on the southern flank of the cyclone. This cloud, hooked like a scorpion's tail, gives the wind region its name the "sting jet". It is thought that a zone of strong winds, originating from within the mid-tropospheric cloud head of an explosively deepening depression, are enhanced further as the "jet" descends, drying out and evaporating a clear path through snow and ice particles. The evaporative cooling leading to the air within the jet becoming denser, leading to an acceleration of the downward flow towards the tip of the cloud head when it begins to hook around the cyclone centre. Windspeeds in excess of 80 kn (150 km/h) can be associated with the sting jet.〔(Meteorological glossary ) Booty.org, retrieved 2007-17-10〕 It has since been reproduced in high-resolution runs with the mesoscale version of the Unified Model. The sting jet is distinct from the usual strong-wind region associated with the warm conveyor belt and main cold front. There are indications that conditional symmetric instability also plays a role in its formation but the importance of these processes remains to be quantified.〔(Cyclonic storms ) UWERN newsletter, retrieved 2007-17-10〕 One North Atlantic storm, Cyclone Tilo (November 6–11, 2007) has also been analysed and found not to display a sting jet, despite displaying strong surface winds and a fractured cold front.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「sting jet」の詳細全文を読む スポンサード リンク
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