Abstract:
Three severe convective storms occurring between 19:00 and 21:00 on 14 May 2002 in Changde area, Hunan Province are analyzed based on the new generation (Doppler) weather radar data. These severe storms led to heavy damage, producing wind gust as high as 26 m/s, 30 mm diameter large hails and tornado, in consistency with the radar observations. Among the three convective storms, two are supercell storms and one is squall line. The mesocyclones associated with the two supercells are identified. Both supercell storms produce the Three-Body Scatter Spike (TBSS), with the value of the reflectivity core over 70 dBz. A TWS (Tornadic Vortex Signature) associated with the second supercell storm is identified. Both the Three-Body Scatter Spike (TBSS) and Tornadic Vortex Signature (TVS), associated with large hails and tornado, respectively, have been observed for the first time in China, and large hails and tornado have been confirmed by the surface reports. Research results indicate that the TBSS can be used as a nowcasting index of large hails and high wind.