Research notes and updates from the team.
During February 2025, negative sea surface temperature (SST) anomalies declined over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.35 °C. Also, the weekly-averaged SST anomalies in the NINO3.4 region were 0.0 °C for the week centered on Mar 05, 2025. This indicates the weakening of the ongoing La Niña conditions in the equatorial Pacific Ocean.
Read more →During January 2025, negative sea surface temperature (SST) anomalies intensified slightly over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.71 °C. However, the weekly-averaged SST anomalies in the NINO3.4 region were -0.6 °C for the week centered on Feb 05, 2025. This indicates the ongoing La Niña conditions in the equatorial Pacific Ocean.
Read more →During December 2024, negative sea surface temperature (SST) anomalies intensified over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.62 °C. The weekly-averaged SST anomalies in the NINO3.4 region were -0.7 °C for the week centered on Jan 08, 2025. This indicates onset of La Niña conditions in the equatorial Pacific Ocean.
Read more →During November 2024, slightly negative sea surface temperature (SST) anomalies persisted over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.14 °C. The weekly-averaged SST anomalies in the NINO3.4 region were -0.6 °C for the week centered on Dec 11, 2024. This indicates an ongoing ENSO-neutral state in the equatorial Pacific Ocean.
Read more →During October 2024, slightly negative sea surface temperature (SST) anomalies persisted over the central-eastern equatorial Pacific Ocean, leading to a NINO3.4 anomaly index value of -0.28 °C. The weekly-averaged SST anomalies in the NINO3.4 region were -0.3 °C for the week centered on Nov 06, 2024. This indicates an ongoing ENSO-neutral state in the equatorial Pacific Ocean.
Read more →Notes: The IRI seasonal forecasts of precipitation and temperature issued this month are based on an objective calibration procedure that combines the NCEP-CFSv2, CanSIPS-IC4, COLA-RSMAS-CESM1, GFDL-SPEAR, and NASA-GEOSS2S models. The climatological base period for normal is 1991-2020. The SST anomalies cited below refer to the OISST.v2.1 SST data set.
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