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By means of conventional weather data and new generation weather radar data in June 2008 at Chengde, two coldvortex weather events are compared and analyzed. It is found that an upperlevel cold vortex and a lowerlevel mesoscale shear line are the common influencing systems; severe convective weather caused by the easternMongolia cold vortex is related to the moving track of the cold vortex; the configuration of the wind fields at lower and upper levels and the chimney index are used to determine the size of the vertical wind shear; such factors are highly indicative to severe weather warning as the shape, strength, moving speed, vertical structure characteristics of Doppler radar basic reflectivity, as well as the moving directions of the mesoscale convergence lines, adverse wind areas, vertical shear lines, zerospeed lines on the average radial velocity fields; the jumps and drastic reduction of VIL values have also great significance, VIL increasing gradually with development at the convection stage and decreasing after the beginning of convective weather.