Summary

Issued 06 January

• The El Niño Southern Oscillation (ENSO) remains neutral. International climate models forecast ENSO-neutral until at least autumn 2020.
• The Madden-Julian Oscillation is currently very weak. Forecasts suggest the MJO will rapidly reform and strengthen in the next few days, and enter the western Pacific in mid-January.
• The Intertropical Convergence Zone (ITCZ) was weaker than normal in the far western Pacific and in the central Pacific. The South Pacific Convergence Zone (SPCZ) was enhanced as a thin band from northeast of the Solomon Islands, southeast to the Pitcairn Islands and near normal over Fiji and Tonga. The SPCZ was suppressed to the northeast and southwest of these locations.
• Sea level in December was higher than normal in the equatorial and south Pacific. All COSPPac countries experienced positive sea level anomalies with the highest anomalies situated close to the equator, spanning from Nauru to all three Kiribati EEZs with an anomaly greater than 15 cm.
• Coral Bleaching Alerts span Nauru and the Kiribati Gilbert Islands. The 4-week Coral Bleaching Outlook favours bleaching continuing across Nauru and Tuvalu and developing in the central and eastern Solomon Islands region.
• For January to March 2020, SCOPIC and the APEC Climate Centre multi-model favour below-normal rainfall for Yap in the Federated States of Micronesia, southern Papua New Guinea and eastern Solomon Islands. Above-normal rainfall is favoured for the northern Gilbert Islands in Kiribati.
• Two tropical cyclones have formed to date in the southwest Pacific region. These were Severe Tropical Cyclone Rita to the east of the Solomon Islands and Vanuatu on 22 November and Tropical Cyclone Sarai to the north of Fiji on 23 December. For the western tropical Pacific region the anomaly probability of tropical cyclone occurrence over 5-25 January is near normal.