Evolution of the 2006–2007 El Ni o: the role of intraseasonal to interannual time scale dynamics

The relationship between monthly mean sea surface temperature (SST) anomalies in the commonly used El Ni o regions and precipitation for 44 stations in Perú 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 Ni o 1+2, Ni o 3.4, and Ni o 4 regions are available. Prediction of SST anomalies in El Ni o regions is routinely available from Climate Prediction Center, NOAA, with reasonable skill in the El Ni o 3.4 region, but the prediction in El Ni o 1+2 region is less reliable. The feasibility of using predicted SST anomalies in the El Ni o 3.4 region to predict SST anomalies in El Ni o 1+2 region is discussed.