Introduction

El Niño/Southern Oscillation (ENSO)

• The Equatorial Pacific Ocean is currently in a neutral ENSO state, with remnant anomalies from the La Niña event that has just concluded. Most dynamical and statistical climate models suggest ENSO neutral conditions for late autumn and early winter. Some long range models indicate El Niño could develop by austral spring.

Tropical cyclone activity for 2011/12 season

• Normal or below average tropical cyclone (TC) activity was forecast for the February – April period. Overall, 5 – 8 TCs were expected for the whole season.
• April was a relatively quiet month in the southwest Pacific, with no named TCs having formed. The seasonal total for the ICU forecast region at the end of April was five named storms.

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

• Below normal rainfall is forecast for Tuvalu, while normal or below normal rainfall Tokelau, the Tuamotu archipelago, Wallis and Futuna, the Society Islands, Samoa and the Northern Cook Islands.
• Normal or above normal rainfall is expected for Eastern Kiribati, Western Kiribati, Papua New Guinea, Fiji, Vanuatu and Tonga.
• The sea surface temperature anomalies associated La Niña are muted relative to prior months, and the forecast persists a 'weak' La Niña-like pattern across the southwest Pacific.