一次雷暴天气潜势预报与中尺度分析

马远卫 雷崇典 杜浩 田杨媚

摘要 利用常规气象觀测资料、T639数值预报产品FY-2E卫星云图及相关定量产品，分析了2014年7月29日陕北出现的一次局地雷暴天气过程，基于雷暴发生的三要素讨论了中尺度不稳定与雷暴发生之间的关系、抬升与触发的异同以及天气系统与雷暴抬升机制之间的关系，并对产生雷暴机制的物理量和有利于雷暴发生的中尺度环境进行分析。结果表明，雷暴是在条件不稳定层结下产生的，位势不稳定的建立有利于雷暴机制的形成与发展；雷暴发生区形成较强的湿度梯度，有利于雷暴发生区产生垂直环流。上升区在湿空气区，下沉区在干区，这个垂直环流圈的进一步发展反过来又维持了湿舌，是强对流的一种触发机制。有利的中尺度环境场和边界层辐合线的形成是雷暴的触发机制。高层的辐散场与短波槽的配置，有助于低层850 hPa和地面辐合线触发雷暴。

关键词 雷暴；潜势预报；中尺度；物理量

中图分类号 S16；P458 文献标识码 A 文章编号 0517-6611（2017）29-0180-04

Potential Prediction and Mesoscale Analysis of a Thunderstorm Weather

MA Yuanwei，LEI Chongdian，DU Hao et al

（Yanan City Meteorological Bureau， Yanan，Shaanxi 716000）

Abstract Using the conventional meteorological observation data， T639 numerical prediction product FY2E satellite cloud image and related quantitative products， the process of local thunderstorms in northern Shaanxi on July 29， 2014 was analyzed，based on the three elements of thunderstorm， the relationship between mesoscale instability and thunderstorms， the similarities and differences between lifting and triggering， and the relationship between weather system and thunderstorm mechanism were discussed，and analyzed the physical quantity of the thunderstorm mechanism and the mesoscale environment which was favorable to the occurrence of the thunderstorm.The results showed that the thunderstorm was generated under the condition of unstable stratification， and the establishment of instability was conducive to the formation and development of thunderstorm mechanism.The thunderstorm area had a strong gradient of humidity， which was favorable for the vertical circulation of the thunderstorm.Rising support in the wet air area， sinking area in the dry area， the further development of the vertical circulation circle in turn maintained the wet tongue， which was a strong convection trigger mechanism.Favorable mesoscale environmental field and boundary layer formation were thunderstorm triggering mechanisms.The highlevel diffuse field and shortprofile configuration helped the lower 850 hPa and ground convergence lines to trigger thunderstorms.

Key words Thunderstorm；Potential prediction；Mesoscale；Physical quantity

作者簡介 马远卫（1973—），男，陕西咸阳人，助理工程师，从事强对流天气研究。

收稿日期 2017-07-26

雷暴泛指深厚湿对流，常伴有雷雨、大风、冰雹等，可以不伴有雷电活动。雷暴（深厚湿对流）生成三要素是指静力不稳定、水汽和抬升条件[1]。随着我国短临预报的开展，雷暴生成三要素已被广泛接受，以“配料法”[2]为思路的雷暴产生环境条件的研究逐渐增多；在业务预报中，虽然“配料法”能够化繁为简，使预报思路的物理概念清晰，但又面临一些具体问题，特别是条件不稳定与位势不稳定的异同与判据。……