CAJ | 학술논문

2011年7月26日石家庄市出现一次暴雨冰雹天气，其特点是500 hPa及以上高空强冷空气导致高空形势在12 h内发生剧变，短波槽快速南下，致使探空观测和数值预报失灵。本文对其他监测资料进行分析，发现这种剧烈变化的天气有明显特征：卫星云图上河套北部逗点云系尾长而粗壮，有向南发展趋势，云系后部的暗区表明干冷空气侵入，与低层暖湿空气形成对流云，尾部断裂表明冷空气加速南下。单站要素变化显示，石家庄地面假相当位温比正常值高了8℃，出现异常不稳定能量。强对流天气发生在假相当位温密集带内，能量中心假相当位温最高达到90℃以上，100 km内假相当位温温差超过25℃，最大降雨出现在假相当位温密集带内。雷达回波呈西南—东北带状排列，前部最大强度为65 dBZ，强回波前形成阵风锋，正负最大速度均超过20 m／s，飑线自西向东移动，它的移向和发展程度决定降雨和冰雹的路径和强度。石家庄市区风向转变和形成地面辐合线分别较降水起始时间提前21 min 和30 min。
2011년7월26일석가장시출현일차폭우빙박천기，기특점시500 hPa급이상고공강랭공기도치고공형세재12 h내발생극변，단파조쾌속남하，치사탐공관측화수치예보실령。본문대기타감측자료진행분석，발현저충극렬변화적천기유명현특정：위성운도상하투북부두점운계미장이조장，유향남발전추세，운계후부적암구표명간랭공기침입，여저층난습공기형성대류운，미부단렬표명랭공기가속남하。단참요소변화현시，석가장지면가상당위온비정상치고료8℃，출현이상불은정능량。강대류천기발생재가상당위온밀집대내，능량중심가상당위온최고체도90℃이상，100 km내가상당위온온차초과25℃，최대강우출현재가상당위온밀집대내。뢰체회파정서남—동북대상배렬，전부최대강도위65 dBZ，강회파전형성진풍봉，정부최대속도균초과20 m／s，박선자서향동이동，타적이향화발전정도결정강우화빙박적로경화강도。석가장시구풍향전변화형성지면복합선분별교강수기시시간제전21 min 화30 min。
A torrential rain and hail stroke Shijiazhuang on July 26,2011. The strong and cold air flow on 500 hPa and above resulted in sharp shifts of synoptic situation at high altitude in twelve hours,with short wave trough moving southward rapidly,which caused the failure of radiosonde observation and numerical forecast. Based on other monitoring data,obvious characteristics of the dramatic chan-ging weather were analyzed. Firstly,according to satellite images,the comma cloud above the Great Bend of the Huanghe River had long and stout tail,with a tendency of developing southward. The dark area at the rear part of clouds indicated the intrusion of dry cold air,which developed into convective clouds with warm and moist air at low altitude. The tail fracture suggested the acceleration of mov-ing southward of cold air. Secondly,the Shijiazhuang single station element variation showed that the surface potential pseudo equiva-lent temperature was 8 ℃ higher than the normal value,which indicated abnormal instability energy. Strong convective weather with the largest precipitation was located in the intensive zone of pseudo equivalent potential temperature,which reached 90℃ at the energy center. The difference of pseudo equivalent potential temperature within 100 km was more than 25 ℃. Finally,the radar echoes ar-ranged zonally from the southwest to the northeast with the strongest echo of 65 dBZ in the front. Gust front formed before the strong echo,its maximum positive and negative speed were both larger than 20 m/s. The squall line moved from west to east and its path and intensity ditermined the path and intensity of precipitation and hail. The transformation of wind direction and formation of surface con-vergence line were 21 min and 30 min ahead of the precipitation,respectively.