基于新型观测资料分析台风"烟花"短时强降水成因OACSTPCD

This paper used high-resolution gridded datasets and observation data from a matrix of automatic detection equipment,including national meteorological stations,wind profile radars,microwave radiometer,laser precipitation particle spectrometer,and S-and X-band dual-polarization Doppler radar,to analyze the causes of the short-time heavy precipitation in Nanjing brought on by Typhoon"In-Fa"(2106)from various scales and further discuss the applications of varied detection equipment in improving the capability of short-time forecasts and nowcasting.Results show that:(1)the background circumstances for the generation of short-time heavy precipitation were favorable due to the storm wind structure,environmental vertical wind shear,vapor transport,saddle-field pattern,and symmetric tropical cyclone circulation.Enhanced water vapor density,strengthened cloud water content,a thickening saturated wet layer,and rapidly developing strong boundary layer low-level jet and vertical wind shear in interaction with inversion temperature triggered and sustained the severe precipitation.The generation of lower concentration,regular-shaped,medium-large size pure liquid raindrops after the warm rain collision and coalescence process with a high concentration of small raindrops resulted in the generation of short duration intense precipitation with low echo mass,strong intensity,and high precipitation efficiency.(2)The formation and intensity of heavy precipitation were efficiently indicated using new-sounding data.The enhanced storm organization structure was characterized by the temperature,humidity,and wind vertical profile about 1.5-4 h in advance,and the micro-physical parameters predicted the intensity and features of precipitation with a lead-time of 0.5 h.(3)Although the echoes of heavy precipitation obtained by X-band radar were weak in intensity,short in range,and obviously attenuated,it was still possible to gather information about the microphysical properties of cloud-water particles below the boundary layer,which can significantly improve the ability to monitor the lower layers in conjunction with S-band radar.