Research On Lightning Forecast Of The Five Cities In Southern Jiangsu

In this paper, we analyzed the characteristics of the thunderstorm weather in southern Jiangsu, including annual variation of lightning activity,distribution of each months and the spatial distribution of the lightning activity in southern Jiangsu. Based on a thunderstorm weather process in Jiangsu on July3,2012, in combination with the cloud characteristics, we analyzed the performance characteristics of the convective parametersin each areas.According to the water vapor condition、unstable stratification、lifting condition、 temperature conditions and other factors which the necessary conditions of thunderstorm, in condition with practical experience and physical meaning, we selected12indexes such as ic、si、 tt、li、ji、a, brn、tcl_t、ssi、h0c、dt₅8and pw. We used the NCEP data to calculate each convective indexes, analyzing correlation of convective indexes with lightning activities based on the9150samples in five cities in southern Jiangsu at8:00from April to September,2001-2010. The seven indexes such as pw, ji, si, tt, ssi, tcl-t, dt₅8are selected as predictors and forecasting equations are set up in approach of plot-box statistics and double sequence correlation coefficient analysis.The fitting test based on the8230samples from April to September,2001-2009shows an average PO is18.7%, the average FAR is23.9%and the average TS（Threshold Success） index is61%.Trail prediction based on the920samples including31thunderstorm days and153non-thunderstorm days from April to September at2010shows an average TS（Threshold Success） index of58.25%.