La Nina Has Generated; Intensifying Rapidly!

Fig. 1-2: The daily Nino34 SSTA has cooled dramatically as moderate La Nina intensity has developed.

Discussion: The daily Nino34 SSTA has cooled to -1.06C (Fig. 1) qualifying as a moderate La Nina signature. The cooling is remarkable with a 30-day change of a stunning -0.81C (Fig. 2). The subsurface is as impressive as a strong cool anomaly intensified across the equatorial East Pacific (Fig. 3) and upper ocean heat east of the Dateline has cooled to a peak for the evolution of La Nina during 2024 (Fig. 4). The catalyst to the steady and now rapid cooling of the past 1-2 months is positive phase southern oscillation index (+SOI) identifying a La Nina climate pattern causing up-welling trade winds to increase and bring cool waters to the eastern equatorial Pacific surface (Fig. 5). As a reminder, and a possible influence on new January forecasts, the winter La Nina temperature bias is warmer than normal in the East (Fig. 6).

Fig. 3-6: The subsurface equatorial East Pacific Ocean has cooled during the past month as La Nina fuel increases dramatically. Southern oscillation index is increasingly La Nina-like positive phase. The La Nina climate bias is warm in the East U.S.