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The continuing heavy pollution cases from 2004 to 2008 in Beijing are calculated, and the weather patterns without duststorm weather during the continuing heavy pollution episodes are analyzed. It is concluded that continuing heavy pollution processes exhibit distinct seasonality, including mainly sand/dust pollution in spring and nonsand/dust pollution in falltowinter season; during continuing heavy pollution episodes, the nonsand/dust continuing pollution processes correspond with lowvisibility weather, such as heavy fog, light fog, haze and smoke, etc.; in the later periods, pollution processes correspond with gale or precipitation weather, especially the longtime heavy pollution events frequently occurring during heavy fog weather. The circulation characteristics during continuing pollution episodes without sand/dust weather are: there is zonal circulation in the upper air, a warm ridge at 850 hPa, a weak pressure field on the ground; serious pollution is often found under the saddlefield pattern; continuing heavy pollution days are frequently related with regional pollution.