A study on the forecast model of winter precipitation type in Liaocheng based on physical parameters

Abstract

Abstract In this study, 46 physical parameters are first calculated by using the hourly ground observational data of Liaocheng Airport station and the daily sounding data of Xingtai station and Zhangqiu station in the winters of 2016–2020. After the significance test of the correlation coefficients between the physical parameters and the precipitation types, six physical parameters that could be used in the operational weather forecast at Zhangqiu station and Xingtai station are selected by the methods of box‐plot and skill score based on the distribution characteristics of physical parameters under different precipitation types. Moreover, the judgment criteria for the winter precipitation forecast in Liaocheng are obtained by analyzing the indication effect and thresholds of each physical parameter in different precipitation types. In addition, a forecast model of winter precipitation type in Liaocheng is established by using the extended membership function transformation method with the sounding data from the nearest upstream and downstream stations. The verification with observations shows that the forecast accuracy is above 85% and the model performs quite well. We hope this study can provide a good reference for related operational forecasts in the areas without local sounding data or numerical forecast product receiving.

Keywords

• forecast model
• membership function
• physical parameters
• precipitation type
• skill score