| 摘要: |
| 【目的】为提高雷暴大风天气气象服务的及时性和预报准确率，提升观测预报互动的快速响应能力。【方法】利用天气形势，卫星云图，单、双偏振雷达衍生产品等，对湘潭地区2022年4月24日和7月28日（以下简称“4·24”过程和“7·28”过程）2次不同强度灾害性雷暴大风天气过程进行对比分析。【结果】（1）“4·24”过程主要影响系统以动力作用为主；“7·28”过程以热力作用为主。（2）“7·28”过程出现在午后，较出现在傍晚的“4·24”过程生命史更短。（3）2次过程中近地面均有弱风层的存在，易产生局地强风暴；“7·28”过程中CAPE值和K指数较“4·24”过程的能量弱，而对流抑制有效位能CIN较大，更有利于不稳定能量的保存。（4）“4·24”过程以单体型下击暴流为主，“7·28”过程以阵风锋为主。（5）双偏振雷达观测表明冰雹融化或大雨滴蒸发冷却有助于下沉气流加速作用。【结论】研究成果能有效提供关于风暴发展过程以及强度变化的关键信息，为预测同类天气事件提供科学依据，大幅提升雷暴大风天气的气象服务能力。 |
| 关键词: 雷暴大风；天气形势；雷达特征；不稳定能量 |
| DOI： |
| 投稿时间：2024-04-24修订日期：2024-07-09 |
| 基金项目:2023年湖南省气象局创新发展专项《关键环境阈值在湘潭致灾雷暴大风过程中的应用》（CXFZ2022-QNZX06） |
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| Analysis of Two Thunderstorm Gale Events of Different Intensities: Synoptic Background and Radar Characteristics |
| hening,DAI Jin,HUANG Juan,,HUANG Xinyi,ZHANG Yue |
| (Xiangtan Meteorological Office of Hunan Province) |
| Abstract: |
| In order to improve the timeliness and forecast accuracy of meteorological services in thunderstorm gales weather, and enhance the interactive rapid response capability of observation and forecast, based on the synoptic situation, satellite images, Doppler radar and Dual-Polarization radar data, two severe thunderstorm and gale processes with different intensities that occurred in Xiangtan region on April 24 and July 28, 2022 (hereinafter referred to as “4·24” process and “7·28” process) are compared and analyzed. The results show that: (1) The thunderstorm gale process on April 24 was mainly driven by dynamic factors, while the process on July 28 was mainly fed by thermodynamic factors. (2) The July 28 process appeared in the afternoon and had a shorter lifecycle than the April 24 process, which occurred around evening. (3) Both processes featured low-level weak wind layers near the ground, conducive to localized severe storms; the CAPE value and K index in the July 28 process were weaker than those in the April 24 process, while the larger CIN was more conducive to preserving unstable energy. (4) The April 24 process was dominated by single-cell downbursts, whereas the July 28 process was dominated by gust fronts. (5) Dual-Polarization radar observations indicate that melting hail or evaporation cooling of large raindrops contributed to the acceleration of descending airflows. These features found in this study can effectively provide key information about the developing process and intensity change of thunderstorm gales, provide a scientific basis for predicting similar weather events, and help improve the meteorological service capability in thunderstorm gale weather. |
| Key words: thunderstorm gale; synoptic situation; radar characteristics; unstable energy |
