Analysis of a Heavy Fog in Kunming-Changshui Airport Under the Influence of a Quasi Stationary Front

Based on the routine upper air sounding data and AWOS data,synoptic pattern and the meteorological character analysis is applied on a 26 ~ 31 heavy fog. The results show that heavy fog occurs during the cold air strengthens,statics,and weakens when Changshui airport located in the cold area of the front. When the fog sustained,double inversion layers and deep high reality humidity layer can be find in the upper air,and the base of inversion layer is low. The results also show that the surface wind direction is north-east,and the wind speed is 2 ~ 5m/s when the fog lasted,the fog will get clear when the surface wind direction turns from north-east to south-west.