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ENSO Quick
Look IRI ENSO Update / Forecast Technical ENSO Update IRI Probabilistic ENSO Forecast ENSO Prediction Plume Monthly archive ENSO Update15 February 2007SummaryAs of mid-February the El Niño conditions are rapidly diminishing. Sea surface temperature (SST) anomalies remain approximately 0.5C above average in the central equatorial Pacific, but warm SST anomalies in the eastern Pacific have declined and in parts have been replaced recently by below-average temperatures. Based on the latest observations and forecasts, there is a 60% probability of ENSO-neutral conditions for February-March-April 2007.General DiscussionThe 2006/07 El Niño event, which peaked in early December 2006, is now declining rapidly. Temperatures near the dateline dropped from 1.5C to 0.5C above average between December and January, and remain near 0.5C above-average. SSTs in the eastern Pacific experienced significant cooling over the past month, dropping from 1.5C above average to -1.0C below average in the vicinity of 125W. The declining warm anomalies are due in part to the resurgence of the easterly Trade Winds moving colder waters from east to west. Also, below-average temperatures in the subsurface equatorial Pacific have moved from west to east, eroding the warm conditions, and leading to cold SSTs as the easterly winds draw the cold subsurface waters to the surface.Most of the models have not captured the rate of return to neutral conditions over the last couple months, rather indicating a slow decline of the El Niño. Out of a large set of dynamical and statistical forecast models, the majority predict ENSO-neutral conditions by March/April 2007. Overall, based on model forecasts and current observations of the ocean surface and subsurface, the probability of a La Niña has increased beyond the climatologically expected odds to 30% over over the next few months. The probability of maintaining El Niño conditions through the next couple months has dropped to 10%. The probability of ENSO-neutral conditions is most likely throughout the forecast period, with a 60% likelihood. Note 1 - Only models that produce a new ENSO forecast every month are included in the above statement.
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