Below-normal rainfall is likely across much of the western Pacific in the coming months as El Niño strengthens, according to the World Meteorological Organization’s Pacific Regional Climate Centre Network, putting island nations that are already short of water under further strain. The outlook, issued on October 23 following the 19th Pacific Islands Climate and Ocean Forum, covers November 2026 to January 2027.
Below-normal rainfall is likely from Palau to the Marshall Islands and from central and southern Papua New Guinea to southern French Polynesia, according to the network. Along the equator, a wetter season than usual is expected from Nauru to eastern Kiribati. Papua New Guinea, Solomon Islands, Vanuatu, Fiji and Tonga have already reported water shortages linked to persistently low rainfall between May and October.
The strongest El Niño since 1950
There is a high chance that this El Niño will be the strongest recorded since 1950, the network said. It is expected to persist into the March to May 2027 period, and some countries are likely to feel its effects after the event ends. Above-normal air temperatures are likely across most of the western and central tropical Pacific and from Papua New Guinea south-east to New Caledonia.
The warning matches the global picture from the WMO, which forecasts that sea surface temperatures in the Niño 3.4 monitoring region will average about 3.8 degrees Celsius above normal between November 2026 and January 2027, with the peak expected in December. El Niño has officially reached the “very strong” intensity category, with an anomaly of plus 2.0 degrees during the August-September-October quarter, according to the US National Oceanic and Atmospheric Administration.
Cyclones and water shortages
Normal to above-normal tropical cyclone activity is expected in the south-west Pacific from November 2026 to April 2027, adding to the risks for island nations already dealing with water shortages. The WMO has issued a joint call with the UN humanitarian office for anticipatory action: pre-positioning food and water, expanding early warning systems, and releasing money before a disaster rather than after it.
The Pacific outlook was issued days before COP31 opened in Antalya, Türkiye, on November 9, where the WMO’s State of the Climate Update 2026 said global average surface temperatures between January and September 2026 reached about 1.47 degrees Celsius above the pre-industrial average. For the Pacific islands, the immediate concern is practical: water tanks running dry, crops failing, and health risks rising as the dry months set in.
Related reading: WMO Warns 2026 Among Four Warmest Years as El Niño Strengthens
