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A statistic analysis is made based on a large amount of observations during typical heavy air pollution days from January 2002 to December 2004 in Shijiazhuang.The temporal and spatial distribution of typical heavy air pollution days,the corresponding characteristics of meteorological elements,and three favorable synoptic patterns are revealed.The results show that most of typical heavy air pollution days take place in the heating period and have continuity in the temporal distribution;on dusty pollution days,there are strong winds,low humidity and positive pressure variation,and on non-dusty pollution days,there are weak winds,high humidity and stable stratification(temperature inversion,high Richardson number,etc.);and a weather pattern with the highest occurrence probability of heavy pollution days,owing to the special topography of Shijiazhuang,is(identified.) Some useful hints for forecasting heavy pollution days are presented.