山西雷暴大风雷达产品统计学特征及预警提前量研究

为认识统计山西雷暴大风的雷达产品特征，做好其预报预警，利用2013—2017年4—9月高空探测资料和地面观测资料以及多普勒雷达资料对山西39次雷暴大风过程进行研究。根据500 h Pa环流形势将其分为四大类型：西北气流型、冷涡型、西风槽前型、副热带高压（简称“副高”）切变型。统计分析了不同环流背景下雷暴大风的雷达产品特征及其预警提前量。结果表明：（1）块状孤立对流单体是任一环流背景下山西雷暴大风的主要雷达回波形态。（2）副高切变型雷暴大风的最大回波强度、回波顶高、最大垂直积分液态水含量值最高，冷涡型最低。（3）低层径向速度大值区对雷暴大风的指示意义最明显，预警提前量最多，可提前30 min以上。（4）雷暴大风发生时，有阵风锋和逆风区出现，但出现次数极少。研究结果对利用雷达产品预警山西雷暴大风提供参考依据。

Study on Statistical Characteristics and Early Warning Advance of Thunderstorm Gale Radar Products in Shanxi

Based on the upper air observation data, surface bservation data, Doppler radar data and important weather reports in Shanxi from April to September 2013 to 2017, 39 cases of thunderstorm gale processes were counted out. According to the 500hPa circulation situation, they were divided into four types: Northwest air flow type, cold vortex type, front of West Wind trough type and subtropical high shear type. The radar echo characteristics (type, intensity and structure) and early warning advance of thunderstorm gale under different circulation backgrounds were statistically analyzed. The results show that: (1) Under any circulation background, the block isolated convective cell is the main radar echo pattern causing thunderstorm gale in Shanxi, which accounts for the most proportion of thunderstorm and gale in Shanxi; (2) In the comparison of typical radar echo characteristics of thunderstorm gale, the average maximum echo intensity, average echo top height and average maximum VIL of Subtropical high shear thunderstorm gale are the highest, and the characteristic values of cold vortex type are the lowest; (3) In different circulation backgrounds, the high value area of low-level radial velocity is the main typical radar echo feature, and the early warning advance is the most, which can be 30 minutes or more in advance. (4) When thunderstorm and gale occur, gust front and upwind area appear, but the occurrence times are very few.