El Niño/La Niña Update (February 2009)

Conditions resembling La Niña developed in December 2008, but they are 

already weakening and are not expected to herald a prolonged basin-wide 

La Niña event. Indeed, most assessments indicate that a transition back to 

neutral conditions is expected to occur over the next couple of months. One 

interpretation is that this has been a brief redevelopment of the La Niña event 

that prevailed through the latter part of 2007 and into the first half of 2008. 

Nonetheless, the La Niña-like conditions are having significant consequences 

for some current climate patterns, and impacts may continue in some regions 

over the next month or two. By March-May 2009, forecasts suggest that the 

most likely outcome is near-neutral conditions basin-wide across the tropical 

Pacific. The likelihood of El Niño or La Niña development through the 

remainder of 2009 is considered to be essentially unpredictable at this stage, 

with neither event considered more likely than the other.