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In May 2025, the sea surface temperature (SST) anomaly map (top left) indicates cooler SST anomalies in the tropical Pacific (i.e., Niño 4), with the most prominent cooling centered in the eastern Pacific. In contrast, warmer SST anomalies are more evident in the coastal Niño regions (i.e., Niño 1+2), reflecting a persistent neutral SST trend from earlier months.

Warm SST anomalies are also observed in the Philippine Sea, North Pacific, and the monitored northern and southern regions of the Tripole Pacific Index (TPI).

In the Indian Ocean, warmer SST anomalies are observed in the tropical eastern and western Indian region (i.e., EIO), which indicates no considerable dipole anomalies. In general, the tropical Indian Ocean-wide SST anomalies (i.e., IOBW) were warmer than normal. Lastly, the tropical North Atlantic (i.e., TNA) also has no prominent SST anomalies.

The maps on the right (top to bottom) indicate the observed SST for May 2025 and the climatological normal from 1991 to 2020, providing context for the SST anomaly maps.