Abstract:
According to the climatic characteristics of convective parameters, the probability of occurring convective weather can be estimated ahead of time, so forecast accuracy will be improved. Based on the sounding data of 17 ground stations in Shijiazhuang and Xingtai from June to August in 2004-2005, climatic average values of convective parameters (CAPE, SI, KI and IC) were calculated, and then average value of each convective parameter in thunderstorm day and strong storm day was given. The results indicate that climatic characteristics of convective weather are different in the different months and in the different intensities. Furthermore, convective parameters of daily 4 time levels in July of 2006 are calculated, and the relationship between these parameters and weather in Shijiazhuang are analyzed. It found that CAPE and SI can reflect some strong convective characteristics. The upper-air sounding records at 0200 and 1400 (BST) can make up the limitation of overtime interval from 0800 to 2000 (BST), which is significant to improve the abilities of short-term and nowcasting forecast.