Island Climate Update 175 - April 2015

Sea surface temperatures anomalies in the Equatorial Pacific are maximum around the international Dateline and reflect weak El Niño conditions in March 2015.

Sea surface temperature (SST) anomalies in the tropical Pacific intensified significantly around the international Dateline during March 2015 and are currently showing a pattern consistent with weak ‘central Pacific’ or ‘Modoki’ El Niño conditions.

The ensemble of global climate models for rainfall that are used in METPI show an area of higher than normal rainfall associated with the SPCZ position.

The dynamical model forecasts indicate that the central equatorial Pacific is likely to experience above normal rainfall in April – June 2015. In contrast, regions in the western Pacific south of the Equator, as well as the south eastern Pacific are expected to experience reduced rainfall. Below normal rainfall is forecast for Fiji, the Marquesas, Papua New Guinea and Vanuatu.

Based on rainfall anomaly classification over the past six months and forecast rainfall anomaly classification over the next 3 months.

Sources of South Pacific rainfall data