Global Seasonal Climate Update for January-February-March 2025

Sea-surface temperature anomalies in the Niño 3.4 and Niño 3 regions are predicted to decline slightly during January-March 2025 but stay in ENSO-neutral conditions. Farther west in the Niño 4 region, the sea-surface temperature anomaly is also predicted to stay near-zero. The strength of the IOD index is also predicted to be near-zero. In the equatorial Atlantic, SSTs are predicted to stay positive in both the northern (NTA) and the southern (STA) regions during the season with a prediction for larger positive anomalies for NTA. 

Figure 1. Probabilistic forecasts of surface air temperature and precipitation for the season January-March 2025. The tercile category with the highest forecast probability is indicated by shaded areas. The most likely category for below-normal, above-normal, and near-normal is depicted in blue, red, and grey shadings respectively for temperature, and orange, green and grey shadings respectively for precipitation. White areas indicate equal chances for all categories in both cases. The baseline period is 1993–2009.

Building on the anticipated persistence of above-normal sea-surface temperatures across most ocean basins outside the near-equatorial eastern Pacific Ocean, the prediction is for above-normal temperatures over most land areas for the JFM 2025 period. A few exceptions to this widespread warmth include land areas in the vicinity of the Bering Sea and the Gulf of Alaska, Baja California. Extensive areas of large increases in probabilities for abovenormal temperatures include almost the entire South America below the equator, the Caribbean, Central America, southwest and extreme northeast parts of North America, between 10^o S – 10^o N over Africa extending into the southern regions of Arabian Peninsula, northeast region of the Indian subcontinent, the Maritime continent, New Zealand, and the Arctic regions north of 60^o N. Regions with moderate to weaker increase in probabilities for abovenormal temperatures include Europe, between 30^o – 60^oN over Asia, and northern and southern regions of Africa. In coastal areas of southern South America and extending north along the west coast to just north of the equator and into the eastern Pacific, consistent with the predicted emergence of near-average sea surface temperatures, below- or near-normal temperatures are expected. In general, there is no clear signal over Australia, Greenland, and the northwest part of North America.

Even though sea surface temperatures in the central and eastern Pacific are predicted to be near-average, due to the enhanced east-to-west SST gradient in the equatorial Pacific, like during a La Niña, the predicted rainfall patterns for January-March 2025 are like the typical impacts of La Niña. Enhanced probabilities for near- or below normal rainfall are predicted over a narrow band along or just north and south of the equator extending eastward from 150^o E to the western coast of South American. Below the equator, there is an additional band of enhanced probabilities for below-normal rainfall starting from 150^o W and extending south-eastwards to reach the western coast of South America and crossing into the southern Atlantic. Enhanced probabilities for below-normal rainfall are also predicted over the northeast South America extending into the Atlantic, North America below 45^o N, the Arabian Peninsula extending north-eastward into Central Asia, parts of eastern Asia, and over the Greater Horn of Africa extending into the Indian Ocean to 90^o E. Enhanced probabilities for above-normal rainfall are anticipated over the region centred over the Maritime Continent extending southward to cover Australia and extending further into the western Pacific to 150^o W, southern regions of Central America and the Caribbean, Arctic regions north of 60^o N, the southern parts of the Indian subcontinent, and a belt along 60^o S in the Southern Hemisphere. Other regions of enhanced probabilities for above-normal rainfall include a band off the coast of eastern Asia, extending north-eastward to the Bering Sea and the Gulf of Alaska.