A new approach to forecast the typhoon´s accumulated rainfall in Taiwan by using satellite data

When Typhoon Morakot (2009) swept across Taiwan, the severe devastation inflicted by the torrential rainfall was unprecedented. The unfortunate destruction stemmed from the large amount of precipitable water the typhoon carried, coupled with the long period of time Taiwan was under its influence. Although typhoon forecasting has been improved notably over the years, it remains a difficult challenge to make timely and accurate rainfall forecasts, which is crucial to saving lives and reducing damage. Consequently, it continues to be an important task for researchers to develop a quick and efficient typhoon accumulated rainfall estimation method. In this study, the Rainfall Potential Analog Forecasting technique (RaPAF) is proposed in predicting the accumulated rainfall distribution when a typhoon makes landfall in Taiwan. In the case study of Typhoon Morakot (2009), it is proven that the method not only provided a more accurate accumulated rainfall distribution prediction, but the probable mapping of maximum precipitation areas was also close to the actual observations.