三门峡一次冰雹天气多普勒雷达资料分析

Analysis of the Doppler Radar Data of a Hail Weather in Sanmenxia

利用常规气象资料和多普勒天气雷达资料,从天气形势、物理量场和回波演变特征等方面对2011年7月17日发生在三门峡的一次冰雹天气过程进行了分析。结果表明:本次过程在天气形势上属于华北冷涡型,高空冷空气的侵入对不稳定能量的释放起了触发作用。在多普勒天气雷达资料上表现为单个单体强对流风暴,最大反射率(DBZM)≥60 dBz、回波顶高ET明显跃增、风暴顶高度TOP和最大反射率所在高度HT的跃增与降雹时间有24 min的提前量,降雹发生在DBZM≥60 dBz、TOP和HT减弱阶段、ET和DBZM最大阶段;降雹前垂直积分液态含水量(VIL)和垂直积分液态含水量密度具有明显的跃增,本次过程中二者的预警提前时间为12 min;逆风区和冰雹指数出现"POS"报警对降雹具有一定的预报预警指示意义。

Using conventional meteorological data and Doppler weather radar data on July 17, 2011 in Sanmenxia, a hail weather process was analyzed from the weather situation, the physical quantity field and the echo evolution characteristics. The results showed that： the process belonged to cold vortex type in north China and the upper cold air intrusion played a triggering role on the release of unstable energy. It was a single monomer strong severe convective storm from Doppler weather radar data. The maximum reflectivity （DBZM） which was over or equal to 60 dBz, and the jump interment of echo top （ET）, storm top height（TOP） and the maximum reflectivity height （ET） had 24 rain in advance with hail time. Hail occurred in the period of the maximum reflectivity （DBZM） was over or equal to 60 dBz, TOP and HT were at weakening stage, ET and DBZM were at maximum stage. The value of vertical integrated liq- uid water （VIL） and VIL density had a sharply increasing before the failing large hail; the warning time of this hail was 12 min. Adverse wind area and hail index alarm on the ＂POS＂ had an important implica- tion of hail forecasting and early warning.