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Based on the data from the Doppler radar, two wind profilers in Baodi and Xiqing, the tower in Tianjin, as well as NCEP/NCAR 1°×1° reanalysis data, radiosonde data,intensified automatic surface observation data and automatic station minute data, a thunderstorm case in Tianjin on 8 June 2014 is analyzed. The results show: (1) It is a thunderstorm gale case of the northwestern current type, in which the wind vertical shear with a large temperature lapse rate was favorable for the occurrence of disastrous gale. (2) This case experienced three stages: bow echo complex, gust front, and cell bow echo. The intensity of the thunderstorm wind was related to the falling time and the height of the echo core: the higher extension of height, the shorter the falling time, the stronger of the thunderstorm. (3) The rapid movement of a strong cold pool was direct cause of the bow echo complex. The wind profiler data indicate that the intrusion of dry cold air was at 23 km in the bow echo complex, with a 10 minute lead time for wind gust in the surface. The surface mesoscale convergence line matching with surface highly unstable region triggered the thunderstorm at the stage of the cell bow echo. (4) When the gust front approaching, the rising flow was in coexistence with the sinking flow; the sink flow began at the boundary layer below 15 km with the maximum up to 09 m〖DK〗·s-1 at 630 to 750 m. The downward propagation of the sinking velocity peak indicated the emergence of the gust about 20 minute in advance, while the upward was above 2 km in the middle and lower troposphere.