A region of suppressed convection is likely in the southwest Pacific encompassing Samoa, Niue, Tonga, Fiji, New Caledonia, the Southern Cook Islands, the Society Islands, the Austral Islands and Papua New Guinea. Near to below average rainfall is expected for all of those islands, except for Samoa, which is expected to receive below average rainfall. Near normal rainfall is forecast for the Northern Cook Islands, the Tuamotu Archipelago, and Pitcairn Island. Enhanced convection is likely along the Equator extending from Western to Eastern Kiribati, with an expectation of above normal rainfall. Near or above normal rainfall is also forecast for Tokelau and Tuvalu. No clear precipitation guidance is offered for Vanuatu, Wallis and Futuna, and the Solomon Islands.
The global models are continuing to show elevated temperatures in the near equatorial Pacific sea surface. Some anomalies a have strengthened from past months, and a diffuse warming is seen in many models for the eastern half of the southwest Pacific Ocean. Above average sea surface temperatures are forecast for Eastern and Western Kiribati. A region of near or above average sea surface temperatures is forecast around Papua New Guinea, New Caledonia, Tokelau, and the Solomon Islands, the Northern Cook Islands, the Southern Cook Islands, the Marquesas, the Austral Islands, and Pitcairn Island. Average or below average SSTs are forecast for Fiji and Tonga. Near normal SSTs are forecast for the remainder of the southwest Pacific.
The multi-model ensemble forecast skill confidence for this seasonal rainfall outlook is moderately high for most countries. In the past, the average region-wide hit rate for rainfall forecasts issued in November is 64%, 3% higher than the long–term average for all months combined. The SST forecast confidence is mostly high for this period.
(Rainfall outlook map for November 2009–January 2010)
(SST outlook map for November 2009–January 2010)