FXUS24 KWNC 091324
PMDENS
El Nino/Southern Oscillation (ENSO) Diagnostic Discussion
NWS Climate Prediction Center College Park MD
900 AM EST Thu 9 May 2024

NOTE: figures mentioned in the discussion are available on
the internet at HTTP://WWW.CPC.NCEP.NOAA.GOV

ENSO Alert System Status: El Nino Advisory / La Nina Watch

Synopsis: A transition from El Nino to ENSO-neutral is
likely in the next month. La Nina may develop in June-August
(49percent chance) or July-September (69percent chance).

During April 2024, below-average equatorial sea surface
temperatures (SSTs) emerged in small regions of the eastern
Pacific Ocean. However, above-average SSTs prevailed across
the rest of the equatorial Pacific (Fig. 1). The latest
weekly Nino index values remained between +0.5degC and +0.8degC
in all regions, except for Nino-3 which was +0.3degC (Fig. 2).
Below-average subsurface temperatures held steady during
the month (area-averaged index in Fig. 3), with negative
anomalies extending from the Date Line to the eastern Pacific
Ocean (Fig. 4). Low-level wind anomalies were easterly over
the western equatorial Pacific, while upper-level winds were
near average. Convection was near average overall across the
equatorial Pacific Ocean and Indonesia (Fig. 5). Collectively,
the coupled ocean-atmosphere system reflected the continued
weakening of El Nino and transition toward ENSO-neutral.

The most recent IRI plume favors an imminent transition to
ENSO-neutral, with La Nina developing during July-September
2024 and then persisting through the Northern Hemisphere winter
(Fig. 6). The forecast team continues to favor the dynamical
model guidance, which suggests La Nina could form as early as
June-August 2024, with higher confidence of La Nina during the
following seasons. La Nina generally tends to follow strong
El Nino events, which also provides added confidence in the
model guidance favoring La Nina. In summary, a transition
from El Nino to ENSO-neutral is likely in the next month.
La Nina may develop in June-August (49percent chance) or
July-September (69percent chance; Fig. 7).

This discussion is a consolidated effort of the National
Oceanic and Atmospheric Administration (NOAA), NOAA's National
Weather Service, and their funded institutions. Oceanic and
atmospheric conditions are updated weekly on the Climate
Prediction Center website (El Nino/La Nina Current Conditions
and Expert Discussions). Additional perspectives and analyses
are also available in an ENSO blog. A probabilistic strength
forecast is available here. The next ENSO Diagnostics
Discussion is scheduled for 13 June 2024. To receive
an e-mail notification when the monthly ENSO Diagnostic
Discussions are released, please send an e-mail message to:
ncep.list.enso-update@noaa.gov.



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