Tropical Highlights - January 2025

 

During January 2025, sea surface temperatures (SSTs) were below-average across the central and east-central equatorial Pacific (Fig. T18). The latest monthly Nino indices were -0.2C for the Nino 1+2 region, -0.7C for the Nino 3.4 region and -0.6C for the Nino 4 region (Table T2). The depth of the oceanic thermocline (measured by the depth of the 20C isotherm) was below-average across the central and eastern equatorial Pacific (Figs. T15, T16). The corresponding sub-surface temperatures were 1-5°C below-average in the eastern equatorial Pacific (Fig. T17).

 

Also during January, lower-level wind anomalies were easterly over the western and central equatorial Pacific, while upper-level wind anomalies were westerly over the central equatorial Pacific (Figs. T20, T21). Meanwhile, tropical convection was suppressed around the Date Line and was enhanced over Indonesia (Fig. T25). Collectively, these oceanic and atmospheric anomalies were consistent with La Nina conditions.

 

For the latest status of the ENSO cycle see the ENSO Diagnostic Discussion at: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.html