Based on the conventional observations,hourly automatic weather observations and PM2.5 concentrations from environmental monitoring department,the relationship between meteorological elements and PM2.5 concentrations during a continual fog and haze weather in Hebei Province from January 15 to 19,2014 was statistically analyzed.The results show that in the stage of haze,the de-cline of horizontal visibility was mainly caused by PM2.5 ,and the correlation between visibility and PM2.5 concentrations was the best when relative humidity was between 40% and 60%,while the correlation between visibility and PM2.5 concentrations presented a de-creasing tendency when relative humidity increased.In the stage of fog,the correlation between visibility and relative humidity was sig-nificantly better than the correlation between visibility and PM2.5 concentrations.Due to the northwest gales,the average removal rate of PM2.5 concentrations in Hebei Province was 94.3%and the average removal time was 3.7 hours,which could make the IAQI of PM2.5 achieve excellent or good level.What’s more,snowfall to the scavenging effect of PM2.5 concentrations was inferior to gales,and it’s difficult to make the IAQI of PM2.5 fall to excellent or good level.%利用常规气象观测资料及逐小时地面自动气象观测和环境监测部门的PM2．5浓度等资料，对2014年1月15～19日河北省持续雾霾天气期间气象因子与PM2．5浓度的关系进行统计分析。结果表明，PM2．5是造成霾阶段水平能见度下降的主要因素，相对湿度在40％～60％之间时，能见度与PM2．5浓度相关性最好，随着相对湿度的增大，PM2．5浓度对能见度的作用呈减小趋势；雾阶段能见度与相对湿度的相关性明显好于PM2．5浓度值。西北大风对河北PM2．5浓度的平均清除率在94．3％，去除时间平均为3．7 h，可使PM2．5空气质量分指数达到优或良的等级，降雪对PM2．5浓度的清除作用明显小于大风，很难将PM2．5空气质量分指数降到优或良。
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