The Application of Synoptic Stratification to Precipitation Forecasting in the Trade Wind Regime

Abstract

Abstract A 1129-day high quality rainfall dataset was collated, from the months of March to November 1993–97, where trade wind flow predominates across the northeast Queensland tropical coast. This dataset was matched with numerical model fields from the Australian regional limited area model. Synoptic precipitation regimes were identified by subjective classification of a major portion of the development data utilizing radar, surface, and upper-air data. With the aid of classification trees, a series of objective sorting criteria were developed to stratify the numerical model dataset into weather regimes prior to the development of a series of predictive equations for rainfall through screening regression. In addition to raw numerical model output, potential predictors with established links to trade wind precipitation were offered to the regression procedure. Rainfall equations were also developed by seasonal stratification of the development data. Further comparison was made with rainfall occurrence ou...