关键词: 雷暴大风, 气候特征, 变化趋势

Abstract:

Based on the observational data of 9 meteorological stations in Langfang of Heibei Province during 1970 － 2012，the temporal and spatial characteristics，change trends and cycle of thunderstorm gale were analyzed by using trend analysis，moving t test，wavelet analysis and maximum entropy spectrum． Results showed that thunderstorm gale in Langfang mostly occurred at one station，while the whole regional thunderstorm gale appeared only once．Thus，the thunderstorm gales had strong local feature．The regional characteristic of thunderstorm gale was obvious，and thunderstorm gale days in We nan and Dacheng as well as Langfang city were more，while they were least in the north of Langfang．The daily，monthly and annual variation of thunderstorm gale days were significant．The thunderstorm and gale mostly happened from afternoon to midnight，and the occurring time of gale was later than that of thunderstorm generally．The frequencies of thunderstorms lasting about 1 hour and gales lasting 10 minutes were the most．The thunderstorm gale weathers occur from March to October，especially in summer，and the occurring frequency is 73.3%．In the past 43 years，the days of thunderstorm gale decreased significantly，and the decreasing trends at stations in the middle of Langfang were the most significant．The mutation of thunderstorm gale days occurred in 1994，and the significant period was 3.23 years．

Key words:  thunderstorm gale, climatic characteristics, change trend