MESOSCALE RAINBANDS AHEAD OF COLD FRONTS IN NORTH CHINA AND THEIR DYNAMICAL MECHANISMS

摘要

Among 33 cold frontal systems passed over the Beijing-Tianjin-Tangshan area from May to August during1963—1979,there existed mesoscale rainbands in the warm sectors ahead of 31 cold fronts.These rainbands,according to their orientation,movement,formation and development,can be divided into three types:parallel,angulate and perpendicular type.The basic characteristics,sources and propagation of the three types ofrainbands and the severe convective weather associated with the bands are presented.The possible mechanis-ms responsible for the formation and development of the bands are also briefly discussed.