Precipitation Forecast from 10-20 Days by the Method of the Low-Frequency Synoptic Weather Map in Liaoning Province

A new forecasting method, the low-frequency weather map (LFSC), is applied in Liaoning precipitation forecast from 10 to 20 days. By using LFSC, the active characteristics of the low-frequency cyclones and anticyclones are analyzed. Based on their active characteristics, the precipitation processes are forecasted. The forecast results are good in Liaoning region from June to August 2011 and its forecasting period of validity is about 10-20 days. The LFSC method can be applied to predict the precipitation process in the extended-range forecast from 10 to 20 days.