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In April 2025, the sea surface temperature (SST) anomaly map (top left) indicates cooler SST anomalies in the central Pacific (i.e., Niño 4), with the most prominent cooling centered near the International Dateline. In contrast, warmer SST anomalies are more evident in the eastern and coastal Niño regions (i.e., Niño 3 and Niño 1+2), reflecting a persistent SST warming trend from earlier months.

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

In the Indian Ocean, warmer SST anomalies are more pronounced in the tropical western region (i.e., WIO), whereas the tropical eastern region (i.e., EIO) indicates no considerable 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) observed cooler SST anomalies.

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