La Nina Remains Choppy But Subsurface East Pacific is Warming

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Highlight: La Nina stays choppy. Subsurface cool water to sustain La Nina is lowering.

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

Discussion: Whether La Nina ends (or not) during springtime is an extremely important call regarding U.S. springtime precipitation, soil moisture and summer temperature implications. Last week at the surface the Nino SSTA was markedly cooler indicating La Nina regained strength (Fig. 1). La Nina’s SSTA observations in the Nino regions near and east of the Dateline are fluctuating each week as La Nina classification is “unsteady”. The upper ocean heat in February indicates warming took place implying the subsurface cool waters to sustain La Nina is diminishing (Fig. 2). If La Nina fades during spring as many models indicate there is likelihood of a dry spring season for the Great Plains (Fig. 3) and expanding drought risk and a hot summer ahead. If La Nina hangs on a wetter scenario is likely (Fig. 4).

Fig. 2: The upper ocean heat analysis across the equatorial Pacific Ocean indicates some warming in February.

Fig. 3-4: If La Nina fades this spring a dry Central U.S. climate is likely. If La Nina hangs on a wetter pattern is likely.