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应用中尺度气象模式MM5对2006年和2007年12月东部地区进行逐日模拟,并用地面常规观测资料及南京和安庆12h一次的逐日探空资料对模拟的地面及边界层内气象要素进行检验,计算地面和边界层内不同高度的温度、湿度、风向和风速等要素的多种常用统计参数;并分别评估雾发生前和发生时边界层探空的模拟效果。结果表明：（1）MM5模式模拟的地面温度和湿度均较理想,但风速误差较大。温度、相对湿度、风速的观测与模拟的偏差概率分布均呈近正态分布,峰值中心分别为-1.52℃、4.59%和1.92m·s-1,白天模拟效果优于夜间。（2）以南京、安庆两站为例,模拟的08：00（北京时,下同）和20：00边界层内探空基本可靠,但20：00的效果比08：00好;模拟效果均随高度上升而变好;且南京站边界层内温度、湿度的模拟效果优于安庆站,但安庆站风的模拟效果优于南京站。（3）以南京站为例,雾发生前和发生时温度、湿度模拟效果较平均情况差,风速模拟较其他模拟时段无明显变化。（4）南京、安庆冬季近地层逆温发生频率都比较高,常见多层逆温,MM5模式能再现近地层逆温,但有高估的倾向,且对边界层中上部逆温模拟效果不佳。此外,敏感性试验的结果表明,模拟方案中地面负的温度偏差不是由近地层高垂直分辨率所致。“,”To assess the performance of MM5in simulating the meteorological parameters in the planetary boundary layer(PBL),Meteorological elements of PBL in east China in December of 2006and 2007 were simulated by MM5.The simulation results were assessed objectively by the ground convention observation data and daily sounding data at Nanjing and Anqing stations at 08:00and 20:00.Some common used statistical parameters of temperature,relative humidity,wind direction and wind speed at surface and different levels in PBL were calculated.And simulation effect of sounding in PBL before fog and during fog were assessed,respectively.The results show that:(1)the simulated temperature and relative humidity were reliable at the ground level,but the error of simulated wind speed was more.Frequency distributions of the biases between simulated and observation temperature,relative humidity and wind speed are nearnormal distribution,and peak values are-1.52℃,4.59% and 1.92m·s-1,respectively.The simulation effect in daytime is better than in nighttime.(2)Take Nanjing and Anqing stations for example,the simulated sounding in PBL at 08:00and 20:00were acceptable,and the effect at 20:00was better than that at 08:00.Simulation effect of temperature and relative humidity in PBL at Nanjing station was better than that at Anqing station,but wind speed at Anqing was better.(3)Take Nanjing as an example,simulation effect of temperature and relative humidity during the fog and before fog days were worse than normal,but wind speed had no significant difference.(4)The frequently of temperature inversion near surface were more than 40%in Nanjing and 30%in Anqing in winter.Temperature inversion near surface reappeared but overrated by model,and simulation effect in middle-to-upper boundary layer was not good.In addition,According the results of numerical sensitivity test,the high vertical resolution near surface was not necessary the bias of negative temperature at the ground level in modeling scheme.