Skip Navigation Links 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center

HOME > Expert Assessments > Climate Diagnostics Bulletin > Forecast Forum
Forecast Forum - July 2006

          The canonical correlation analysis (CCA) forecast of SST in the central Pacific (Barnett et al. 1988, Science, 241, 192‑196; Barnston and Ropelewski 1992, J. Climate, 5, 1316‑1345), is shown in Figs. F1 and F2. This forecast is produced routinely by the Prediction Branch of the Climate Prediction Center . The predictions from the National Centers for Environmental Prediction (NCEP) Coupled Forecast System Model (CFS03) are presented in Figs. F3 and F4a, F4b.  Predictions from the Markov model (Xue, et al. 2000: J. Climate, 13, 849‑871) are shown in Figs. F5 and F6.   Predictions from the latest version of the LDEO model (Chen et al. 2000: Geophys. Res. Let., 27, 2585‑2587) are shown in Figs. F7 and F8.  Predictions using linear inverse modeling (Penland and Magorian 1993: J. Climate, 6, 1067‑1076) are shown in Figs. F9 and F10. Predictions from the Scripps / Max Planck Institute (MPI) hybrid coupled model (Barnett et al. 1993: J. Climate, 6, 1545‑1566) are shown in Fig. F11.  Predictions from the ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in Fig. F12.  Niño 3.4 predictions are summarized in Fig. F13, provided by the Forecasting and Prediction Research Group of the IRI.

The CPC and the contributors to the Forecast Forum caution potential users of this predictive information that they can expect only modest skill.


            ENSO-neutral conditions are expected to continue for the next one to three months, with  a 50% chance that weak warm episode (El Niño) conditions will develop by the end of 2006. 



           The atmospheric circulation and precipitation patterns during July 2006 were consistent with ENSO-neutral conditions in the tropical Pacific. However, equatorial surface and subsurface temperature anomalies increased during the month, with SST anomalies greater than +0.5ºC observed in most of the equatorial Pacific between 130ºE and 140ºW (Fig. T18). As a result, positive SST anomalies were observed in all of the Niño regions (Table T2 and Fig. T5).   During July, low-level (850-hPa) easterly winds were weaker than average across most of the equatorial Pacific (Fig. T 20), and the Southern Oscillation Index (SOI) was negative for the third consecutive month (Fig. T1).  Beginning in February the basin-wide upper ocean heat content increased, and since early April positive anomalies have been observed.  Positive upper-ocean heat content anomalies are usually a precursor to warm (El Niño) episodes. 

          The value of the Oceanic Niño Index (ONI; 3-month running mean average of SST anomalies in the Niño 3.4 region – computed using the Extended Reconstructed SST version-2 data set) for May - July 2006 is 0.1°C, which indicates ENSO neutral conditions. The statistical and coupled model forecasts range from ENSO-neutral to weak warm (El Niño) episode conditions for the remainder of 2006 and into early 2007 (Figs. F1, F2, F3, F4a, F4b, F5, F6, F7, F8, F9, F10, F11, F12 and F13). The forecasts are consistent with the recent build up in upper-ocean heat content along the equator, indicating a trend toward warm-episode conditions.  In the absence of any strong intraseasonal (Madden-Julian Oscillation – MJO) activity, a continued slow trend toward warm-episode conditions is expected.  Therefore, ENSO-neutral conditions are expected to continue for the next one to three months, with a 50% chance that weak warm episode (El Niño) conditions will develop by the end of 2006.

            Weekly updates of SST, 850-hPa wind, OLR and features of the equatorial subsurface thermal structure are available on the Climate Prediction Center homepage at:


NOAA/ National Weather Service
NOAA Center for Weather and Climate Prediction
Climate Prediction Center
5830 University Research Court
College Park, Maryland 20740
Page Author: Climate Prediction Center Internet Team
Page last modified: November 17, 2005
Information Quality
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities