Climate and Oceans Support Program in the Pacific (COSPPac) Bulletin

Issued 17 October 2025

• The El Niño Southern Oscillation (ENSO) remains neutral while a negative Ocean Dipole continues.
• The Madden Julian Oscillation (MJO) is currently in the western Pacific. International models forecast the MJO models to stall, before potentially weakening.
• In August, the Intertropical Convergence Zone (ITCZ) was active and close to its normal position. The South Pacific Convergence zone was active and also close to its normal position.
• Sea surface temperatures (SSTs) near the New Zealand region were the warmest on record for October.
• The Coral bleaching alert on 13 November shows patches of 'Alert Level 1' over FSM.
• For November 2025 to January 2026, the models agree that above normal rainfall is likely or very likely over Palau, CNMI, Guam, most of FSM, southern RMI, and a band stretching south-eastwards over PNG, most of Solomon Islands, New Caledonia, Vanuatu, Fiji (Excluding Rotuma), Tonga, Niue, southern American Samoa, southern Cook Islands, and southern French Polynesia. Below normal rainfall is likely or very likely over northern RMI, and in a band stretching south-eastwards from Nauru to Kiribati (Gilbert, Phoenix, and Line Islands), Tuvalu, Tokelau, northern Cook Island., northern French Polynesia, and Pitcairn Islands.
• The weekly tropical cyclone forecasts from the ACCESS-S model shows significantly increased risks for Palau, FSM, Guam, CNMI, RMI, Philippines, and south China sea region, for the 26 November to 02 December. There is reduced risk during the period 19 November to 02 December during the latest model run.