ENSO Quick
Look
IRI ENSO Update / Forecast
Technical
ENSO Update
IRI Probabilistic ENSO
Forecast
ENSO Prediction Plume
Monthly
archive
ENSO Update
16 April 2008
Summary
La
Niña conditions have weakened in the equatorial Pacific.
Below-average sea surface temperatures (SSTs) still exist
across central equatorial Pacific, but they have been trending toward
neutral since February 2008. There is a 60% probability of
maintaining La Niña conditions over the coming season.
General Discussion
The La Niña conditions that have been in place since
August 2007 appear to have peaked in February 2008, and are now
trending towards ENSO-neutral conditions. The below-average SSTs
are weakening in the central and eastern equatorial Pacific, while
above-average SSTs exist in the far eastern Pacific. The equatorial
heat content is increasing. Also, the Southern Oscillation index has
been decreasing, suggesting a weakening of the atmospheric
manifestation
of La Niña. On the other hand the remaining easterly wind
anomalies and below-normal temperatures may be enough to retain La
Niña classification over the next month or two.
Out of a large set of dynamical and statistical forecast models, most
models indicate continued weakening of the La
Niña conditions through
2008, most of them reaching ENSO-neutral SSTs by mid-2008.
Overall, based on model forecasts and current observations of the ocean
surface and subsurface, the probability of a La Niña is
estimated at 60% for the Apr-May-Jun season in progress. The
probability of
returning to
ENSO-neutral conditions increases to the climatological value of 50% by
mid-2008.
Note 1 - Only models that
produce a
new ENSO forecast every month are included in the above statement.
Top of Page
|
