Structure and evolution of precipitation cores in an isolated convective storm observed by phased array weather radar

Abstract

phasd array wathr radar (PWR) can complt on volum scan in 30 s, thus nabling us to obtain high spatiotmporal rsolution cho intnsitis and wind filds of storms. sing its rapid scanning capability, w in-vstigatd th volution of a convctiv storm in dtail. o dscrib th volution of convctiv storms, w usd th following dfinitions. h prcipitation cll is dfind as a thr-dimnsionally contiguous rgion of 40 dBZ or gratr. h prcipitation cor is dfind by a thrshold of positiv dviation gratr than 7 dBZ, which is a diffrnc from th avrag rflctivity during th matur stag of th cll. n updraft cor is dfind as an updraft rgion of 1 m s−1 or strongr at a hight of 2 km. n isolatd convctiv storm was obsrvd by two PWRs on 7 ugust 2015 in th inki istrict, wstrn apan. h storm was judgd as a singl cll, according to th abov dfinition. W idntifid nin prcipitation cors and fiv updraft cors within 49 min in th matur stag of th cll. long-lasting updraft cor and its branchs movd southwstward or southastward. round ths updraft cors, th prcipitation cors wr gn-ratd succssivly. h updraft cor with th longst duration lastd 73.5 min; in contrast, th liftims of th prcipitation cors wr from 4.5 min to 14.5 min. h prcipitation cll was maintaind by th succssiv gnrations of updraft cors which liftd humid air associatd with a low-lvl southwstrly inflow. h total amounts of watr vapor inflow supplid by all th idntifid updraft cors wr proportional to th volums of th prcipitation cll, with a corrlation cofficint of 0.75. hus, th xtrmly high spatiotmporal rsolution of th PWR obsrvations provids us with nw vidnc that an isolatd convctiv storm can b formd by mul-tipl prcipitation cors and updraft cors.