The Diurnal Variation of Thunder Events in China

The diurnal variation of thunder events and its possible mechanisms in the recent 30 years in China are investigated using the data from 517 weather stations in China over the period from 1980 to 2008(a lack of data in 2000).The results show that thunder events peak from the late afternoon to the evening.The diurnal variation of thunder events is influenced by topography and has the following types: two or more peaks in plain areas,a single peak in mountainous areas,a nocturnal peak in Sichuan basin areas,and a daytime peak in the coastal areas of Guangdong and Guangxi provinces.Furthermore,the diurnal variation of thunder events in the last two areas above is affected to some extent by the diurnal variation of wind field.The characteristics of diurnal variation of thunder events vary with seasons.The highest proportion of thunder occurrence occurs from 06UTC to 12UTC in summer in the North China Plain and Sichuan Basin.The proportion of daytime thunder occurrence is higher in summer and autumn than that in spring in the coastal areas of Guangdong and Guangxi and the mountainous areas in Southeast of China.