Analysis and Prediction on Features of Climate Changes of Thunderstorm over Ruian City in the Late 47 Years

Based on daily observation data of thunderstorm in Ruian during 1960～2006,the characteristics of thunderstorm were analyzed,such as annual,seasonal and monthly variability,the first and the last day of thunderstorm occurrence.The number of thunderstorm days was predicted by method of Markov chain model.The result showed that the average annual number of thunderstorm days in Ruian was 43 d,the average first date of thunderstorm was in February 26th,and the average last date was in October 16th.The seasonal variability features of it was obvious,the incidence of thunderstorm showed a declining trend since 1988.The prediction made by Markov chain model indicated that the days of thunderstorm would be from 32 d to 38 d in 2007.Finally,the suggestions about applications of the character and the prediction of thunderstorm days were put forward.