MenuMain navigation

Island Climate Update 256 - January 2022

The NINO3.4 Index anomaly (in the central equatorial Pacific) over the last month was -0.68˚C, near the La Niña threshold. The monthly Southern Oscillation Index (SOI) was +1.3 and the three-month average SOI was +1.0, both in the La Niña range.

Upper-oceanic heat content continued to be below normal in the central and eastern equatorial Pacific, associated with the peak of a La Niña event. In the subsurface, anomalies of -1˚C to -2˚C continued at depth in the central and east. In the west, a substantial warm pool of water (+3˚C to +4˚C) developed between 150-200 m depth.

The Southwest Pacific Convergence Zone was again displaced southwest of its climatological position, over northern PNG to about New Caledonia or Fiji, consistent with La Niña.

La Niña conditions remain favoured during January-March (80% chance). Between April-June, there is a 70% chance for the re-emergence of ENSO neutral conditions.

During July-September, ENSO neutral is favoured at a 50% chance.

On 10 December, Tropical Cyclone Ruby formed in the Coral Sea. The system strengthened into a high-end category 2 system, with sustained winds of 110 km/h just before making landfall on northwestern New Caledonia on 14 December. Gusts as high as 162 km/h lashed parts of the Island as hundreds of homes lost power. 405 mm of rainfall was recorded over 48 hours at Kouaoua, in Northern Province in New Caledonia. In addition to Ruby, there have been three other cyclones in the basin so far this season, with 9-12 expected in total.

The MJO is currently over the western Pacific and is predicted to pulse across the Pacific again in mid-to-late January. This gives an elevated change of tropical cyclone formation in the region during this time.



placeholder image