【摘要】 利用常规观测资料和中尺度模式(WRF-V2.2)预报产品,对2009年2月3日宁夏中北部雪后大雾天气过程进行分析.结果表明,雪停天气转晴、温度快速回升、积雪融化使近地面层空气接近饱和、风速较小,为大雾的形成提供了有利的条件;大气层结稳定、水汽充沛、地面的长波辐射冷却是形成辐射雾的主要原因;深厚逆温层的维持对大雾持续起着决定性作用.更多还原

【Abstract】 The weather,which was a heavy fog after snow in the middle north of Ningxia on February 3,2009,is analyzed by using routine meteorological data and mesoscale model forecast products(WRF-V2.2).The result shows that the favorable condition for forming heavy fog weather is that the snowy day fairs up,temperature rises rapidly,air vapor approaches saturation above ground surface for the melt snow and less wind speed.The main reason is stable atmospheric stratification,plentiful water vapor and long-wave radiative cooling.Maintenance of deep inversion layer plays a decisive role in the continuous heavy fog.更多还原