El Niño – related precipitation variability in Perú

Abstract. The relationship between monthly mean sea surface temperature (SST) anomalies in the commonly used El Nino regions and precipitation for 44 stations in Peru is documented for 1950–2002. Linear lag correlation analysis is employed to establish the potential for statistical precipitation forecasts from SSTs. Useful monthly mean precipitation anomaly forecasts are possible for several locations and calendar months if SST anomalies in El Nino 1+2, Nino 3.4, and Nino 4 regions are available. Prediction of SST anomalies in El Nino regions is routinely available from Climate Prediction Center, NOAA, with reasonable skill in the El Nino 3.4 region, but the prediction in El Nino 1+2 region is less reliable. The feasibility of using predicted SST anomalies in the El Nino 3.4 region to predict SST anomalies in El Nino 1+2 region is discussed.