A Revision and Evaluation of the IMFIA-UR Seasonal Rainfall Forecast Method based on the ENSO state

From September 1997, IMFIA have issued a forecast for regional precipitation in four regions in Uruguay. Founded in the documented relationships betwen ENSO and rainfall in southeastern South America and spetially in Uruguay we built a forecast statistical in nature and based in the current state of ENSO using SST indices as predictor. We focus on regionally averaged seasonal precipitation for particular seasons for we previously know tahat Pacific SST has certain capability in order to forecast rainfall in Uruguay. The forecast is built for each particular season after testing several choices of the statististical parameters scheme (critical values, window defining a subpopulation, etc.( The forecast were issued in the (firstly CPC and later)COLA-ELLF Bulletin standard. A version of the context, methodology, results and preliminary evaluation of these forecast issued during 1997, 1998 and 1999 will be issued.