Research notes and updates from the team.
The SST anomaly in the NINO3.4 region during the Jul–Sep 2025 season was -0.28 °C, and for September, it was -0.44 °C. The most recent weekly average (week centered on October 15, 2025) of the NINO3.4 index was -0.6 °C.
Read more →The SST anomaly in the NINO3.4 region during the Jun–Aug 2025 season was -0.12 °C, and for August, it was -0.33 °C. The most recent weekly average (week centered on September 10, 2025) of the NINO3.4 index was -0.5 °C. While these values remain within the ENSO-neutral range, they reflect a clear cooling trend, indicating that cold conditions are gradually developing in the tropical Pacific Ocean.
Read more →The SST anomaly in the NINO3.4 region during May-July 2025 season was -0.02 °C, and for July, it was -0.06 °C. The most recent weekly average (week centered on August 13, 2025) of the NINO3.4 index was -0.3 °C. The latest seasonal, monthly, and weekly values indicate that the tropical Pacific has been experiencing ENSO-neutral conditions.
Read more →The SST anomaly in the NINO3.4 region during Apr-Jun 2025 season was -0.05 °C, and for Jun 2025, it was +0.04 °C. The most recent weekly average (week centered on July 09, 2025) of the NINO3.4 index was +0.1 °C. The latest seasonal, monthly, and weekly values suggest that the tropical Pacific has been experiencing ENSO-neutral conditions.
Read more →The SST anomaly in the NINO3.4 region during Mar-May 2025 season was -0.03 °C, and for May 2025, it was -0.04 °C. The most recent weekly average (week centered on June 11, 2025) of the NINO3.4 index was -0.0 °C. The latest seasonal, monthly, and weekly values suggest that the tropical Pacific has been experiencing ENSO-neutral conditions.
Read more →The SST anomaly in the NINO3.4 region during the Feb-Apr 2025 season was -0.14 °C, and for April 2025, it was -0.16 °C. The most recent weekly average (week centered on May 14, 2025) of the NINO3.4 index was -0.10 °C. The latest seasonal, monthly, and weekly values suggest that the tropical Pacific has been experiencing ENSO-neutral conditions.
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