Strong El Niño to Drive Global Temperatures Higher: WMO

This was stated in the Global Seasonal Climate Update: Target Season November 2026 and January 2027, prepared in October 2026 by World Meteorological Organization and Korea Meteorological Administration and National Oceanic and Atmospheric Administration, US Department of Commerce

According to the update, the seasonal average Niño 3.4 SST ensemble mean anomaly is forecast to reach approximately +3.8°C during NDJ 2026-27, with the warming trend peaking around December 2026.

The spread among individual forecast systems generally remains narrow, reflecting high forecast confidence. In the Indian Ocean, a positive IOD is predicted to decline toward climatology, yielding a seasonal mean anomaly for ND 2026-27 of +0.3°C.

Meanwhile, the equatorial Atlantic basin is forecast to remain warm, with SSTs in both the North and South Tropical Atlantic staying above normal.

Surface Temperature Outlook for the Next Season

For the NDJ 2026-27 season, multi-model ensemble forecasts project a nearly universal global dominance in the enhancement of probabilities for above-normal temperatures over landmasses.

In the Northern Hemisphere, a large increase in probabilities for above-normal temperatures covers Africa, southern Europe, the Arabian Peninsula, the Indian Subcontinent, Eastern Asia, western coastal parts of North America south of 60°N, northeastern regions of North America, Central America, the Caribbean, and the Arctic Circle north of 60°N.

Model consistency across these regions is moderate to strong. Conversely, a weaker enhancement in probabilities for above-normal temperatures is indicated over parts of northern Asia along 50°N, northwestern regions of North America, and interior regions of Greenland. Over southern parts of North America extending into northern parts of Central America, the predicted signal, and model consistency, are weak.

In the Southern Hemisphere, a strong enhancement in probabilities for above-normal temperatures is centered over Africa, and South America between the equator and 30°S, supported by strong model consistency.

A moderate increase in the probability for above-normal temperatures is predicted over Australia. A weak enhancement in the probability for below-normal temperatures is predicted in the eastern coastal and adjacent interior regions of southern South America with low-to-moderate model consistency.

In the tropics, a large increase in probabilities for above-normal temperatures covers equatorial Africa, equatorial South America, and the Maritime Continent. Over the ocean basins, forecasts reflect the footprint of a strong El Niño event.

Extreme probabilities (exceeding 80%) for above-normal temperatures dominate the equatorial Pacific east of the Date Line, extending eastward to the coast of South America while broadening in its latitudinal extent, with the core of the warm region displaying maximuı model consistency.

A widespread tendency for an increase in probabilities for above-normal temperatures also covers the Indian Ocean and the tropical Atlantic.

In contrast, a region of enhancement for below-to near-normal temperature probabilities is predicted across the subpolar North Atlantic.

Additionally, a distinct zone of enhanced probabilities for below-normal temperatures is centered in the South Pacific subtropical region (between 10°S and 30°S) situated directly south of the core El Niño region, supported by strong model consistency.

Rainfall Outlook for the Next Season

For the NDJ 2026-27 season, multi-model ensemble forecasts project well-structured, large shifts in rainfall probabilities, exhibiting a strong response to the Pacific El Niño. The most dominant feature of the outlook is a strong enhancement in the probability of above-normal rainfall stretching across the central and eastern equatorial Pacific east of the Date Line, backed by strong model consistency.

The core of this rainfall signal is flanked by an extensive region of below-normal rainfall probabilities. This broad dry signal encompasses widespread marine zones, manifesting as strong enhancements in the probability for below-normal rainfall over both the western Pacific and the equatorial Atlantic Ocean, as well as a horseshoe pattern extending into the Northern and Southern Hemispheres starting at around 120°E.

The southern lobe of enhancement in the below-normal rainfall probability stretches across the South Pacific to the southern tip of South America.

There is an enhancement in probabilities for above-normal rainfall extending from the Arabian Peninsula, through Central Asia, and continuing into Eastern Asia, particularly in the coastal and adjacent regions of Eastern Asia.

Across equatorial Africa, the Greater Horn of Africa shows an enhanced probability for above-normal rainfall. There is a weak enhancement in probabilities for below-normal rainfall south of 10°S across parts of southern Africa. The model consistency for shifts in forecast probabilities across Africa is low-to-moderate.

There is an enhancement in the probability for below-normal rainfall covering the southern parts of Central America and the Caribbean, supported by high model consistency. To their north, there is an enhancement in the probability for above-normal rainfall over North America south of 45°N.

There is a weak enhancement in the probability of below-normal rainfall over the northwestern regions of North America, where model consistency is weak-to-moderate.

In South America, a robust enhancement in the probability of below-normal rainfall is centered over the northern regions and extends southward to about 15°S. Farther south, an enhanced probability for above-normal rainfall extends across southeastern South America, giving way to an enhanced probability for below-normal rainfall over the southern tip of the continent.

Across Europe, there is a weak enhancement in the probability for above-normal rainfall. The model consistency is low-to-moderate.

Over Australia, a weak signal for an enhancement in above-normal rainfall is confined to the interior and southern parts of the continent, where the model consistency is moderate.