Abstract:An extremely severe rainfall event occurred in Henan in 18-20 July 2016 (the “7·19” rainstorm) under the influence of vortex and cyclone. The precipitation was mainly concentrated in northern Henan, and the maximum accumulated rainfall was 732 mm observed at Dongmaan Station in Anyang. This paper analyzes the fundamental features of precipitation, large scale circulation and mesoscale system of the “7·19” rainstorm based on the hourly rainfall and surface wind data of automatic weather stations, the composite reflectivity data of SA radar, the conventional sounding data and ECMWF (European Centre of Medium Range Weather Forecasts) reanalysis data. At the same time, this paper also analyzes the physical quantity properties of 71 extreme rain events, which are defined as precipitation ≥100 mm·(24 h)-1 at any representative weather station within selected areas. These severe rainfall events took place in the east of Taihang Mountain in northern Henan. The results show that the topography of Taihang Mountain and favorable large scale circulation under the background of vortex and cyclone provided abundant water vapor and better convergent lifting conditions for the “7·19” rainstorm. The train effect produced by the generation, development and maintenance of mesoscale terrain convergence lines and the movement of multiple surface cyclones are the main cause for the “7·19” severe torrential rain in northern Henan. Compared to the physical characteristics of various extreme rain events, the dynamic factors of “7·19” have obvious features of extremity.