Based on Doppler radar data,meteorological satellite data,automatic weather station data and the NCEP/NCAR(1°×1°) reanalysis data,this paper studies the circulation background,internal structure and evolution of the meso-scale convective systems in a storm rainfall far distant from typhoon in Anhui Province.Results show that:1)The easterly airstream around lower typhoon transports moisture and heat to rainstorm area,which results in the enhancement of atmospheric instability in the mid-latitude area.While the ascending motion in front of the westerly trough is beneficial to the development of low layer convergence and the maintenance of vertical motion in the rainstorm area.2)The strong precipitation process consists of two meso-β scale convective systems(MβCSs),whose generation and maintenance lead to longer time maintenance of the heavy rainfall.3)Radar echoes and ground factors show that the strong precipitation is caused by two meso-β scale convective systems.There are different reasons for the frontogenesis of mesoscale convective system,but the development of convection systems is relevant to the surface mesoscale convergence line and the strengthened mesoscale low pressure.Meso-γ scale strong convection systems are the direct reason of local rainfall peak.4)There is a interaction between the middle latitude synoptical system and the circulation of the typhoon outer region in the two strong precipitation processes.The triggering of low layer cold air and the strengthening of southwest warm and wet airflow in front of the westerly trough enhance the precipitation obviously.5)On the Doppler radar radial velocity images,the strengthening of meso-β scale convective systems is closely related to the strengthening of low layer warm and wet airflow.The formation of meso-γ scale convective systems is caused by small scale wind speed convergence.