关键词: 花穗, 花穗

Abstract: A hail process in Shenyang is analyzed using wind profiler radar data, Micaps data and automatic meteorological observing data. The results indicate that under the background of the cold vortex, upper transverse groove and inversion layer are advantageous to unstable energy accumulation and trigger, which leads to the occurrence of hail. Upper air wind form the northwest to the west indicates that transverse trough is coming. The arrival of the cold air for this hail process is forecasted earlier with wind profiler radar data than with conventional observation data. The change of horizontal wind below 1000 m has good corresponding with time and strength of this hail. Upper level winds speed is ≥12 peaks one hour ago before hail. Upper stream occurs jet momentum transmission 20-25 minutes before hail happens; it provides the dynamic condition for the generation of hail. Hail phase detection height increases significantly, which mainly due to moisture in the air and large amounts of ice particles. In the hail process, ice particles mainly exist below 1900 m. Vertical wind shear strengthens 25 minutes before hail happens, reaches extreme 20 minutes before the hail, and the change of the vertical wind shear is consistent with the change of the jet. The time which the extremum of vertical speed appears corresponds not to the start time of hail. SNR ＞60 dB in lower corresponds to the starting of the hail. The sensitive degree of hail of SNR is higher than that of vertical speed. Vertical speed which is ＞4 m/s and the time of precipitation have a good corresponding relation.