Interesting CPC El Nino Discussion

[Anonymous]

From the Climate Prediction Center.........


Warm episode (El NiZo) conditions continued to weaken during March 2003, as the equatorial easterlies strengthened and SST anomalies decreased throughout the eastern and central equatorial Pacific. Since December, SST anomalies have decreased by more than 2EC in the eastern equatorial Pacific between 130EW and the South American coast (Fig. 1). This decrease has resulted in near normal or slightly below normal SSTs in the region east of 120EW since February. During the same period there has also been a steady decrease in the magnitude and extent of the positive subsurface temperature anomalies, indicating a depletion of the excess warmth in the upper ocean of the equatorial Pacific (Fig. 2). This evolution is typical during the decay phases of warm episodes.

In spite of these trends, significant positive SST anomalies remained in the central equatorial Pacific during March 2003, with anomalies greater than +1EC extending from 170EE to 140EW (Fig. 1, middle panel). Greater-than-average precipitation and cloudiness were found over the western portion of this region, although the departures from average and the spatial coverage have decreased substantially during the last two months (Fig. 3). The Tahiti-Darwin SOI remained negative (!1.0) for the 13th consecutive month, while the equatorial SOI was near zero.

A comparison of the 2002-03 El NiZo episode with previous events in the last 50 years (Fig. 4) indicates that for the equatorial Pacific as a whole the 2002-2003 event was moderate in intensity. The SST departures associated with the event were greatest in the central equatorial Pacific (NiZo 4 and NiZo 3.4 regions) and least in the eastern equatorial Pacific (e.g., NiZo 3 and especially NiZo 1+2). This pattern of anomalous warming, combined with the rapid weakening of the event, had a generally weaker than expected influence on the atmospheric circulation and hence the precipitation and temperature patterns over North and South America during January - March 2003.

Consistent with current conditions and recent observed trends, a majority of the coupled model and statistical model forecasts indicate that near-normal conditions will prevail through September 2003. However, there is uncertainty in this forecast as some forecasts indicate the possibility of continued weak El NiZo conditions while others indicate the development of La NiZa conditions during the second half of 2003.

Source: http://www.cpc.noaa.gov/products/analys ... _advisory/

[Anonymous]

They're still being conservative imo. The CPC did post a good update though.

[cycloneye]

Confirms more and more that el nino will not be a factor this season.