Introduction

El Niño/Southern Oscillation (ENSO)

• Multiple ENSO indicators show La Niña is re-emerging in theEquatorial Pacific Ocean. Many dynamical and statistical climate models suggest La Nina will continue to develop during late spring, and into early summer.

Summary of tropical cyclone activity for 2010 -11 season

• Nine tropical cyclones (TCs) occurred in the SW Pacific region thisseason, with an estimated cost of damages exceeding $3.5 Billion USD.
• The tropical cyclone guidance for the 2011-12 season will be releasedon 18 October and summarised in the next ICU issue.

Multi-model Ensemble Tool for Pacific Island (METPI) rainfall and sea surface temperature forecasts

• Below normal rainfall is forecast for Tuvalu, Tokelau, the Tuamotuarchipelago, Samoa, Pitcairn Island, Western Kiribati and the Northern Cook Islands in the three months ahead.
• Above normal rainfall is expected for Papua New Guinea, Vanuatu,Fiji, Tonga and Niue.
• Below normal sea surface temperatures (SSTs) are forecast forWestern Kiribati and Samoa, while above normal SSTs are expected for the Austral Islands and Tonga.