Rainstorm under a background of deformation field occurred in northern Henan from the night of 8 July 2016 to the next morning. We studied the process from the perspective of potential vorticity with Hourly precipitation data from China automatic meteorological station and CMORPH fusion and NCEP's six-hour reanalysis data. The results show that as the high potential vorticity and cold air move to the southeast the potential vorticity values in north of Henan increase gradually from 20:00 on 8 July to 08:00 on 9 July. The meeting of dry cold air and warm wet air causes the heavy rainfall. When the potential vorticity in northern Henan has decreased and typhoon has weakened, the rainfall attenuates consequently due to the continuous eastward movement of the high potential vorticity and the landing of the typhoon at 14:00 on 9 July. The high potential vorticity near 111°E is transmitted eastward and downward, which increases the potential vorticity over the rainstorm area from 02:00 to 08:00 on July 9. Meanwhile, there is strong water vapor convergence on the surface. The maximum value is located at the upwind slope of Taihang Mountain at the height of 900 hPa. In addition, secondary circulation forms from 400 hPa to surface over rainstorm area and the rising branch corresponds to the rainstorm area. The diagnostic analysis of the potential vortity budget equation shows that the local potential vorticity in the rainstorm area at the height of 500 hPa at 08:00 on July 9 increases, and only the horizontal potential vorticity advection provides a positive contribution.
[1]Anna G, 2012. Midlatitude synoptic meteorology:Dynamics, analysis and forecasting-by Gary Lackmann[J]. Meteorological Applications, 19(4):80-84.
[2]Cao Z, Zhang D L, 2004. Tracking surface cyclones with moist potential vorticity[J]. Advances in Atmospheric Sciences, 21(5):830-835.
[3]Cheng L, Yip T C, Cho H R, 2010. Determination of mean cumulus cloud vorticity from GATE A/B-Scale Potential Vorticity Budget[J]. Journal of the Atmospheric Sciences, 37(4):797-811.
[4]Ding Y H, Ma X Q, 2008. Analysis of isentropic potential vorticity for a strong cold wave during 2004/2005 Winter[J]. Acta Meteorologica Sinica, 22(2):129-142.
[5]Green J S A, Hoskins B J, McIntyre M E, et al, 1987. Comments On 'On the Use and Significance of Isentropic Potential Vorticity Maps' By B. J. Hoskins, M. E. Mcintyre and A. W. Robertson(October 1985, 111, 877-946)[J]. Quarterly Journal of the Royal Meteorological Society, 113(475):401-404.
[6]Haynes P H, Mcintyre M E, 1990. On the conservation and impermeability theorems for potential vorticity[J]. Journal of the Atmospheric Sciences, 47(16):2021-2031.
[7]Hoskins B J, Mc Intyre M, Robertson A W, 1985. On the use and significance of isentropic potential vorticity maps[J]. Quarterly Journal of the Royal Meteorological Society, 111(470):877-946.
[8]Isodoro O, Sheldon J, 1993. A case of downstream baroclinic development over western North America Mon[J]. Weather Review, 121(11):2929-2950.
[9]Li N, Ran L K, Linna, et al, 2017. Potential deformation and its application to the diagnosis of heavy precipitation in mesoscale convective systems[J]. Advances in Atmospheric Sciences, 34(7):894-908.
[10]Ren R, Wu G X, Ming C, et al, 2014. Progress in research of stratosphere-troposphere interactions:Application of isentropic potential vorticity dynamics and the effects of the Tibetan plateau[J]. Journal of Meteorological Research, 28(5):714-731.
[11]Wu G, Yaping C, Tang X, 1995. Moist potential vorticity and slantwise vorticity development (in Chinese)[J]. Acta Meteorologica Sinica, 53(4):387-405.
[12]Zhang P Z, Ding Y H, Guo C S, et al, 1994. A diagnostic study of budget of potential vorticity for cold wave-related anticyclone in east asia[J]. Quarterly Journal of Applied Meteorlolgy, (1):49-56.
[13]丛春华, 陈联寿, 雷小途, 等, 2011.台风远距离暴雨的研究进展[J].热带气象学报, 27(2):264-270.
[14]郭大梅, 杨文峰, 杨帅, 等, 2010.一次强对流天气过程等熵位涡及数值分析[J].干旱区研究, 27(5):793-800.
[15]贾旭轩, 蒋大凯, 张炳川, 2010.2008年7月15日辽宁暴雨等熵分析[J].安徽农业科学, 38(21):11230-11232.
[16]靖春悦, 寿绍文, 贺哲, 等, 2007.台风海棠造成河南暴雨过程的位涡分析[J].气象(4):58-64.
[17]林柏旭, 杨明仁, 2012.纳莉(2001)台风之位涡收支[J].大气科学, 40(1):1-27.
[18]寿绍文, 李耀辉, 范可, 2001.暴雨中尺度气旋发展的等熵面位涡分析[J].气象学报, 59(6):560-568.
[19]寿绍文, 励申申, 姚秀萍, 2003.中尺度气象学[M].北京:气象出版社, 2003:276-285.
[20]王宏, 王万筠, 余锦华, 等, 2012.河北东北部暴雪天气过程的湿位涡分析[J].高原气象, 31(5):1302-1308.
[21]吴迪, 楚志刚, 闫立奇, 2015.东北冷涡发展过程的位涡收支分析[J].高原气象, 34(1):103-112. DOI:10.7522/j.issn.1000-0534.2013.00121.
[22]吴蓁, 范学峰, 郑世林, 等, 2008.台风外围偏东气流中的暴雨及其等熵位涡特征[J].高原气象, 27(3):584-595.
[23]徐晶, 王东生, 杨克明, 2004.2003年7月4-7日淮河流域特大暴雨等熵位涡分析[J].气象, 30(1):33-37.
[24]于玉斌, 姚秀萍, 2000.对华北一次特大台风暴雨过程的位涡诊断分析[J].高原气象, 19(1):111-120.
[25]张元春, 孙建华, 傅慎明, 2012.冬季一次引发华北暴雪的低涡涡度分析[J].高原气象, 31(2):387-399.
[26]赵小平, 沈新勇, 朱晶晶, 等, 2014.2009年豫南一次强暴雨过程的位涡方程诊断分析[J].气象, 40(1):38-47.
[27]周秋林, 闵锦忠, 梅士龙, 2010.浙北地区一次大暴雨过程的等熵位涡分析[J].气象科学, 30(4):475-480.
