La Nina Intensity Is Choppy And Weaker

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Significant warming took place last week across the eastern equatorial Pacific Ocean. The Nino34 SSTA region warmed 0.5C to -0.7C which is just-below the La Nina threshold. The Nino3 and Nino12 regions warmed to neutral phase.

Highlight: La Nina intensity is choppy and weaker.

Fig. 1: The 12-week Nino SSTA observations indicate La Nina intensity is choppy and weakening.

Discussion: Significant warming took place last week across the eastern equatorial Pacific Ocean. The Nino34 SSTA region warmed 0.5C to -0.7C which is just-below the La Nina threshold (Fig. 1). The Nino3 and Nino12 regions warmed to neutral phase. The Nino regional trend is choppy in recent weeks but trending toward weakening La Nina. In the subsurface plenty of cool fuel to sustain La Nina remains east of the Dateline while to the west of the Dateline very warm conditions strengthen (Fig. 2). Weakening La Nina toward neutral ENSO phase is the trend!

Fig. 2: The subsurface equatorial Pacific Ocean temperature anomalies.