Analysis on Atmospheric Anomalous Signals of Winter Low Temperature and Snow-Ice Storms in Southern China

In this study, a total of 23 winter snow-ice storms in southern China were determined based on the homogenized daily minimum temperature series and precipitation datasets at 549 stations from 1960 to 2008. By decomposing atmospheric variables into four components, the synoptic-scale atmospheric anomalies of these storms were analyzed. The centers of negative geopotential height anomalies and negative temperature anomalies were found at 300 hPa and 850 hPa, respectively, when surface weather events occurred. The centers of these anomalies can be traced as early signals to indicate the occurrence of surface snow-ice storm events. On an average, the early signals of 11 major snow-ice storm events were identified 11.2 days earlier.