Seasonal Forecast TCs

A Seasonal Forecast Outlook of Tropical Cyclone Activity has been developed by means of climate-based statistical techniques, for an area covering both Samoa and Tonga. This area is big enough to identify the generation areas as well as local patterns. The model is based on finding the relationship between the sea surface temperature (SST) and the mixed layer depth (MLD) as predictor variables, and the TCs occurrence in the target area. A statistical downscaling method that identifies the relationship between the predictor and predictand, based on weather typing, is developed. This relationship is then used with forecast data to predict TC activity in the area.

Below, an sketch of the general methodology for constructing the model and forecasting the number of expected TCs in the following season is presented.