利用多普勒天气雷达观测资料、风廓线仪资料、加密自动气象站资料、常规观测资料和NCEP 1°×1°再分析资料,对2014年7月23日16:00在成都城区发生的一次局地强对流过程进行了分析.结果表明:晴空太阳辐射增温和低层偏南气流的暖湿水汽输送使得成都附近大气具备对流发展的能量和水汽条件;地面暖平流及成都城市热岛效应,使得成都城区低层抬升作用增强;在弱的垂直风切变环境中,南下阵风锋与成都城区西北部地面中尺度热中心和中尺度辐合线相遇,激发出脉冲风暴并迅速发展,进而产生局地强对流天气;多普勒天气雷达资料显示脉冲风暴强盛时期具有悬垂回波、有界弱回波区、中层径向辐合等强风暴的特征.%To investigate the pulse storm occurred at 06:00 23 July 2014 in the urban area of Chengdu,the data of Doppler radar,wind profile,automatic weather station,conventional observation,and NCEP 1°× 1° reanalysis are synthesized and analyzed.It is demonstrated that the clear sky solar radiation and lowlevel water transportation provide energy and moisture conditions for convection development in Chengdu thereabout.The warm advection and urban heat island of the surface layer enhanced the uplift movement at lower levels over the Chengdu urban area.In the weak vertical wind shear area,when gust front meeting with the mesoscale hot center and convergence line on the ground,the pulse storm occurred and developed.The features of the severe storm can be found from Doppler radar echoes,such as the overhanging echo,boundary weak echo range,mid-altitude radial convergence,etc.
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