关键词: 暴雨, 类型, 概念模型, 预报因子, 阈值, 湘西州

Abstract: Based on the daily precipitation data the 6 h reanalysis data of NCEP/FNL at 1°×1° from national weather stations and automatic meteorological stations in Xiangxi Tujia and Miao nationality autonomous prefecture, the rainstorms from 2013 to 2018 were analyzed. Rainstorm forecast conceptual model was built through the diagnosis of the characteristics of the situation field and the physical quantity and the samples of 2019 was tested. The results showed that during the heavy rain in Xiangxi perfecture, the high-altitude westerly jets were significant, and occurred under a single blocking condition. Weather systems like vortex and shear line concentrated distributed. There was positive correlation between precipitable water and rainstorm. The 700 hPa vertical velocity large value center can better indicate the regional heavy rainfal. The U component at 700 hPa was dominant, while the proportion of U and V components at 850 hPa was basically the same. Futhermore the change of the component has a good reference for the rainstorm forecast in Xiangxi perfecture. （Super） Low-level jets were conducive to the occurrence and maintenance of heavy rain, and special attention should be paid to the wind velocity fluctuation. Regional torrential rain was related well to the low-level convergence, the intensity and scope of the high-level divergence configuration, while the local rainstorm and forecast factors have good relationship.

Key words: rainstorm, type, conceptual model, forecast factors, threshold value, Xiangxi perfecture