CPC and the contributors to the Forecast Forum caution potential users of
this predictive information that they can expect only modest skill.
Alert System Status: La Niņa Advisory
is expected to continue into Northern Hemisphere Spring 2009.
Niņa continued during January 2009, as evidenced by below-average equatorial
sea surface temperatures (SST) across the central and east-central
The January values of the Niņo-4, Niņo-3.4, and Niņo-3 SST indices
were cooler than −0.5°C (Table T2).
Negative subsurface oceanic heat content anomalies (average temperatures
in the upper 300m of the ocean) also persisted east of the International Date
Line, but weakened as positive subsurface temperature anomalies from the western
Pacific expanded eastward into the central Pacific (Fig. T17). Convection remained
suppressed near the Date Line, and enhanced across
Low-level easterly winds and upper-level westerly winds also continued
across the equatorial
Collectively, these oceanic and atmospheric anomalies reflect La Niņa.
majority of the model forecasts for the Niņo-3.4 region indicate a gradual
weakening of La Niņa through February-April 2009, with an eventual transition
to ENSO-neutral conditions (Figs. F1-F13).
Therefore, based on current observations, recent trends, and model
forecasts, La Niņa is expected to continue into the Northern Hemisphere Spring
updates of oceanic and atmospheric conditions are available on the Climate
Niņo/La Niņa Current Conditions and Expert Discussions).