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Oceanic indicators firmly exhibit an El Niño state. Central and eastern Pacific sea surface temperatures (SSTs) con-tinue to exceed El Niño thresholds. Models indicate further warming of the central to eastern Pacific is likely. During September, the trade winds were generally weak across the rest of the equatorial Pacific with some westerlies occurring in the western Pacific.

COSPPac Monthly Climate Bulletin, May 2022.

For October to December 2021, the dynamical models agree on above normal rainfall for Palau, FSM, central Marshall Islands, most of PNG and Solomon Is-lands, New Caledonia, Vanuatu, Fiji, Tonga, Niue, southern Cook Islands and southern French Polynesia. The models also agree on below normal rainfall for northern PNG and Solomon Islands, Nauru, Kiribati, Tuvalu, Tokelau, northern and central Cook Islands, and the northern half of French Polynesia.

For September to November 2021, the dynamical models agree on above normal rainfall for Palau, FSM, southern Marshall Islands, most of PNG, southern Solo-mon Islands, New Caledonia, Vanuatu, Fiji, Tonga, Niue, southern Cook Islands and southern French Polynesia. The models also agree on below normal rainfall for CNMI, Guam, central and northern Marshall Islands, northern Solomon Is-lands, Nauru, Kiribati, Tuvalu, Tokelau, northern and central Cook Islands, and the northern half of French Polynesia.

The sea surface temperature a anomaly pattern in July shows SSTs were close to average across most of the equatorial Pacific Ocean. Coral bleaching status is no stress or no watch for almost all countries with patches of warning for western FSM.

The El Niño Southern Oscillation (ENSO) remains neutral. Climate model outlooks indicate this neutral phase will last at least until September. With little sign of El Niño or La Niña developing, the Bureau's ENSO Outlook status is INACTIVE.

Tropical Pacific Ocean sea surface temperatures have persisted at ENSO neutral values for several weeks. Below the surface, much of the tropical Pacific is now at near average temperatures. Atmospheric indicators are also generally at neutral ENSO levels. The Southern Oscillation Index (SOI) is close to zero, while trade winds are currently being enhanced by the Madden Julian Oscillation (MJO). Only cloudiness near the Date Line continues to show a weak La Niña like signature.

The 2020-21 La Niña is likely to have peaked with respect to atmospheric and oceanic patterns in the tropical Pacific. However, impacts associated with La Niña such as above-average rainfall, are expected to persist in the Western Pacific into early March.

La Niña continues in the tropical Pacific. International climate models suggest it is likely to continue to at least February 2021. • La Niña is likely to have peaked but impacts are expected to persist to March. • A moderate to strong Madden-Julian Oscillation (MJO) pulse is expected to move slowly eastwards into the central Pacific in the next week or two. • The OLR total and anomaly maps suggest the Intertropical Convergence Zone (ITCZ) was less active than normal. The South Pacific Convergence Zone (SPCZ) on the other hand, was active and shifted to the southwest. • The January Rainfall image is dominated by a large area of reduced convection stretching over the western to central equatorial Pacific, with the main centre west of the Date Line. • January Mean Sea Level Pressure (MSLP) anomaly negative anomalies east of about 160° in the tropical Pacific. Positive anomalies were present in the southern sub-tropical Pacific east of Samoa.

The December rainfall image is dominated by a large area of reduced convection stretching over the western to central equatorial Pacific, with the main center west of the date line.