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Using the CINRAD/SA data of Qinhuangdao, three wind profilers in Baodi, Xiqing and Jinghai, 255 meters tower on Tianjin, as well as NCEP/NCAR 1°×1° reanalysis data, radiosonde data of Beijing and Laoting, and the 5minute and Jformat data from basic automatic weather stations, the evolution characteristics of a mesoscale convective system (a missing forecast hail event) that occurred in Tianjin on 22 June 2014 are analyzed in detail The results show: (1) The hailstorm event occurred under the northwest airflow pattern and lowenergy conditionsThe hail region intruded along the rare northeast route (2) The hailstorm cell located at the “rightfalling” point of the ground herringbone convergence line, with the combined action of dry line caused the strengthen of hailstormThe surface strong easterly inflow in the formed stage strengthened the wind speed convergence and the dry lineThe automatic station Jformat data show that the variation of meteorological elements (drop in temperature, raise in pressure, increase the humidity) at the matured stage was greater than those at forming and strengthening stages(3) The establishment of the northeast flow in the lower troposphere which located in the rear inflow zone of the hailstorm advanced 3 hoursThe maintenance and downward transmission of the northeast flow played an important role in the enhancement of the hailstorm cell Different from the rear inflow zone, the northeast flow was stretched from the ground to the boundary layer which located in front inflow zone of the hailstorm, and there appeared reversed changes for a short time of meteorological elements before hailfall, due to the downward airflow dragging and weakening of air suction(4) The storm tracking information displayed that the centroids were 3 to 4 km high, while the echo tops were far higher than the-20 ℃ layerThe height of the maximum reflectivity had three fallsThe vertical liquid water content reached 55 kg〖DK〗·m-2 in the strengthened stage