Systematically analyses were carried out for an abrupt heavy rainstorm in Fuping of Shaanxi province on June 8, 2002.The results show that a meso-scale shear line lying in front of 500 hPa trough is the meso-α-scale system that causes the rainstorm.Southeast jet outside typhoon named Coon located in the ocean surface on the east of Taiwan, extended to Shaanxi province from the sea, and supplied the moisture for the rainstorm.The Huabei anti-cyclonic ridge blocked off the eastward movement of rainstorm from the Qinghai-Xizang Plateau and slowed the local rainstorm.Jet sub-circulation supplied a continuous and powerful updraft.In the low-level wind field, two meso-β-scale cyclones were stable and still, and corresponding to the surface heavy rainfall center.On the infrared images, meso-β-scale convective cloud clusters were like an ellipse.The brightness temperature in the cloud top ranged from-60 to-70 ℃.The strength variation of meso-scale convective cloud clusters is largely related to the strength of sub-circulation.
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