For the seasonal mean spanning January-March 2025, global ocean sea-surface temperature (SST) anomalies were generally above average, except for the equatorial central Pacific near the Dateline1. The Pacific Niño SST index anomalies in the far eastern (Niño 1+2) and the eastern Pacific (Niño 3) were above average, while those in the central Pacific were either near or above average (Niño 3.4 and Niño 4 respectively). Despite weak below-average SST anomalies, oceanic and atmospheric conditions in the equatorial central and eastern Pacific remained somewhat consistent with a weak La Niña. The observed Indian Ocean Dipole (IOD) anomaly was near average. Meanwhile, reflecting the persistent warmth in the tropical Atlantic over the past year, SST index anomalies in both the North Tropical Atlantic (NTA) and South Tropical Atlantic (STA) were above average.
For May-July 2025, sea surface temperature anomalies in the Niño 3.4 and Niño 3 regions are forecast to be near-average condition, indicating a neutral state for the El Niño-Southern Oscillation (ENSO). In the Niño 4 region farther west, sea surface temperature anomalies are also projected to decline to near-average. The Indian Ocean Dipole (IOD) index is expected to be in the negative territory. In the equatorial Atlantic, sea surface temperatures are anticipated to remain slightly above average in both the northern (NTA) and southern (STA) regions.
Consistent with the anticipated continuation of widespread above-normal sea-surface temperatures across most oceans, except for the near-equatorial central and eastern Pacific Ocean, above-normal temperatures are predicted for nearly all land areas. Extensive regions with increased probabilities for above-normal temperatures include most of northern Africa, Madagascar, Asia (except over the Indian subcontinent), South America, the Caribbean, Central America, North America, Australia, New Zealand, and Europe. Areas with the largest increase in the probability of above-normal temperatures include the Arabian Peninsula extending eastward into Eastern Asia; the Maritime Continent; a horseshoe-shaped pattern radiating from the Maritime Continent and stretching north-eastward and south-eastward into the North and South Pacific; above 20°N in South America extending northward to cover Central America, the Caribbean, southern and western part of North America; Europe; northern Africa, and New Zealand. Regions with a weaker enhancement in the probability of above-normal temperatures are expected over the Indian subcontinent, southern Africa, north-eastern Australia, and southern parts of South America.
For May-July 2025 July, in the equatorial Pacific, rainfall predictions are consistent with the enhanced positive east-to-west sea surface temperature gradient that are somewhat like observed during weak La Niña, despite the prediction for Niño indices to be in ENSO-neutral state. Enhanced probabilities for below-normal rainfall are forecast between 150°E and the Dateline along the equatorial Pacific. The northern branch for below-normal probabilities for rainfall extends eastward to the western coast of Central America where it swings northward to cover southwest regions of North America. Probabilities for near-normal rainfall are expected along the equator from the Dateline to western coastal regions of South America. Enhanced probabilities for below-normal rainfall are also predicted over the equatorial Atlantic extending into the northeast extreme of South America; southeastern Pacific along 30°S east of 120°W to the western coastal regions of South America; eastern Europe and western parts of Central Asia. Probabilities for above-normal rainfall are enhanced over the Indian subcontinent; Eastern Asia; the Maritime Continent; northwest South America; equatorial Africa extending northward to 20°N; and a band along 60°S in the southern Pacific Ocean. Over most of Australia, northeastern parts of North America; interior regions in the eastern parts of South America, below 10°S over Africa, western parts of Europe, and northern regions of Asia prediction show no clear signal.
1 https://www.cpc.ncep.noaa.gov/products/people/mchen/AttributionAnalysis/images/Attribution202503.pdf
