Research on Ambient Parameter Indicators of Severe Convective Weather in Weining County
To explore the local indicators of classified severe convective ambient parameters in Weining County and to provide a reference for local severe convective weather forecasting and warning,the ambient parameter characteristics of hail and short-time severer rainfall weather are analyzed based on multi-source meteorological data such as conventional ground observations and L-band radar sounding observations in Weining County from 2014 to 2022.In the meantime,the classification indexes and criterion of severe convection weather are summarized by the percentile method.The results show that the two types of severe convective weather can be distinguished by ambient parameters such as atmospheric precipitable water(PWV),near-surface temperature dew point difference(T-Td),temperature difference between near-surface and 500 hPa(ΔTsur-500),convective effective potential energy(CAPE)and 0～6 km vertical wind shear(VWS').Among them,the forecast indicators of hail are:PWV≥18.6 kg·m-2,ΔTsur-500≥24℃,CAPE≥856 J·kg-1,and VWS'≥5.7 m·s-1;the forecast indicators of short-time severe precipitation are:PWV≥26.7 kg·m-2,near-surface(T-Td)≤4.7℃,ΔTsur-500≥22℃,and CAPE≥1 280 J·kg-1.In addition,the height of the wet bulb of hail at 0℃ layer should be within the range of 4 311～5 078 m,and the layer thickness of warm clouds with short-time severe rainfall should be greater than or equal to 4,356 m.Verification of individual cases of severe convection in 2021-2023 suggests that the forecast accuracies of hail and short-time heavy precipitation are 63％and 68％,respectively.These forecast indicators are instructive for the forecasting of the two types weather.
severe convectionambient parameterclassification indicatorWeining County
NETL
NSTL
万方数据
