Abstract: Based on the theory of dissipative structures, a typhoon rainstorm event, which took place in the coastal zone of Hebei Province on 3-4 August 2012, is analyzed with emphasis on the relationship between the rainfall zone and two diagnostic variables, i.e, the atmospheric removing entropy index and the average generalized equivalent potential temperature in the upper boundary. The results show that: the stable subtropical high and the strong southeast jet outside the typhoon lead to an extreme weather event, associated with local torrential-heavy rain; the removing entropy index changing from high values to lower ones denoted the development of convection leading to the formation of heavy rainfall; the negative entropy flow area covered the main area of strong convection and convection heavy rainfall, and the high entropy air converged in the top of the boundary layer 5-6 hours before the torrential rainfall occurred, also the rainfall areas located near the center of high entropy, which is consistent with the high entropy tongue stretched regions .