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A heavy rain event took place in the northeast of Chongqing from August 31 to September 2 in 2014. An analysis is made of this process by using data of conventional observations, NCEP 1°×1°, automatic station, SWAN products, and wind profile. The results show: (1) The persistent heavy rain was produced in a favorable situation. A trough at high altitudes in north of the subtropical high moved slowly due to exceptionally stable subtropical high on the southern China. Persistent largescale forcing induced by the highaltitude trough and the lowlevel shear line maintained the consequent heavy rainfall. (2) Strong southwest warm air and northeast cold air besides the lowlevel shear line intersected in the northeastern region of Chongqing, which led to obvious frontogenesis. The frontal zone was quasistationary during rainstorms. Different 〖WTBX〗θ〖WTBZ〗se in different levels were beneficial to the increasing of instability in the middle and lower troposphere in the front area. (3) Wind profiler radar displayed that the southwest LLJ significantly enhanced during the rainstorms; LLJ sustained more than 8 hours between 1 km and 3 km; and the maximum wind speed exceeded 18 m/s. Significant high divergence and low convergence existed during the rainstorms. (4) The interaction between wind and terrain increased precipitation significantly. TREC (Tracking Radar Echoes by Correlation) winds show that the southwest flow maintained to the south of the Daba Hill, and the wind direction was nearly perpendicular to the mountain strike, so that the terrain effect increased precipitation in front of the mountain, which induced the heavy rainfall along the strike of the Daba Hill.